Colored glass articles having improved mechanical durability

ABSTRACT

A colored glass article includes greater than or equal to 50 mol % and less than or equal to 80 mol % SiO 2 ; greater than or equal to 7 mol % and less than or equal to 25 mol % Al 2 O 3 ; greater than or equal to 1 mol % and less than or equal to 15 mol % B 2 O 3 ; greater than or equal to 5 mol % and less than or equal to 20 mol % Li 2 O; greater than or equal to 0.5 mol % and less than or equal to 15 mol % Na 2 O; greater than 0 mol % and less than or equal to 1 mol % K 2 O; and greater than or equal to 1×10 −6  mol % and less than or equal to 1 mol % Au. R 2 O—Al 2 O 3  is greater than or equal to −5 mol % and less than or equal to 7 mol %, R 2 O being the sum of Li 2 O, Na 2 O, and K 2 O.

This application claims the benefit of priority under 35 U.S.C. § 119 ofU.S. Provisional Application Ser. No. 63/251,785 filed on Oct. 4, 2021,the content of which is relied upon and incorporated herein by referencein its entirety.

FIELD

The present specification generally relates to glass compositions andglass articles and, in particular, to glass compositions andion-exchangeable, colored glass articles formed therefrom.

TECHNICAL BACKGROUND

Aluminosilicate glass articles may exhibit superior ion-exchangeabilityand drop performance. Various industries, including the consumerelectronics industry, desire colored materials with the same or similarstrength and fracture toughness properties. However, simply includingcolorants in conventional aluminosilicate glass compositions may notproduce the desired color.

Accordingly, a need exists for alternative colored glass articles havinghigh strength and fracture toughness.

SUMMARY

According to a first aspect A1, a colored glass article may comprise:greater than or equal to 50 mol % and less than or equal to 80 mol %SiO₂; greater than or equal to 7 mol % and less than or equal to 25 mol% Al₂O₃; greater than or equal to 1 mol % and less than or equal to 15mol % B₂O₃; greater than or equal to 5 mol % and less than or equal to20 mol % Li₂O; greater than or equal to 0.5 mol % and less than or equalto 15 mol % Na₂O; greater than 0 mol % and less than or equal to 1 mol %K₂O; and greater than or equal to 1×10⁻⁶ mol % and less than or equal to1 mol % Au, wherein: R₂O—Al₂O₃ is greater than or equal to −5 mol % andless than or equal to 7 mol %, R₂O being the sum of Li₂O, Na₂O, and K₂O.

A second aspect A2 includes the colored glass article according to thefirst aspect A1, wherein the colored glass article has a transmittancecolor coordinate in the CIELAB color space, as measured at an articlethickness of 1.33 mm under F2 illumination and a 10° standard observerangle, of: L* greater than or equal to 50 and less than or equal to 100;a* greater than or equal to −15 and less than or equal to 25; and b*greater than or equal to −25 and less than or equal to 25.

A third aspect A3 includes the colored glass article according to thesecond aspect A2, wherein R₂O—Al₂O₃ is greater than or equal to −5 mol %and less than or equal to 1.5 mol %; and wherein b* is greater than orequal to −25 and less than or equal to 10.

A forth aspect A4 includes the colored glass article according to thethird aspect A3, wherein R₂O—Al₂O₃ is greater than or equal to −3 mol %and less than or equal to 1.5 mol %; and wherein b* is greater than orequal to −15 and less than or equal to 7.

A fifth aspect A5 includes the colored glass article according to thesecond aspect A2, wherein R₂O—Al₂O₃ is greater than 1.5 mol % and lessthan or equal to 7 mol %; and wherein b* is greater than or equal to 0and less than or equal to 25.

A sixth aspect A6 includes the colored glass article according to thefifth aspect A5, wherein R₂O—Al₂O₃ is greater than 1.5 mol % and lessthan or equal to 5 mol %; and wherein b* is greater than or equal to 0and less than or equal to 15.

A seventh aspect A7 includes the colored article according to any one ofthe first through sixth aspects A1-A6, wherein R₂O—Al₂O₃ is greater thanor equal to −3 mol % and less than or equal to 5 mol %.

An eighth aspect A8 includes the colored glass article according to theseventh aspect A7, wherein R₂O—Al₂O₃ is greater than or equal to −1 mol% and less than or equal to 3 mol %.

A ninth aspect A9 includes the colored article according to any one ofthe first through eighth aspects A1-A8, wherein the colored glassarticle comprises greater than or equal to 0.0001 mol % and less than orequal to 0.1 mol % Au.

A tenth aspect A10 includes the colored article according to any one ofthe first through ninth aspects A1-A9, wherein R₂O is greater than orequal to 6 mol % and less than or equal to 25 mol %.

A eleventh aspect A11 includes the colored glass article according tothe tenth aspect A10, wherein R₂O is greater than or equal to 8 mol %and less than or equal to 23 mol %.

An twelfth aspect A12 includes the colored article according to any oneof the first through eleventh aspects A1-A11, wherein the colored glassarticle comprises greater than or equal to 0.01 mol % and less than orequal to 2 mol % ZrO₂.

A thirteenth aspect A13 includes the colored glass article according tothe twelfth aspect A12, wherein the colored glass article comprisesgreater than or equal to 0.1 mol % and less than or equal to 1.5 mol %ZrO₂.

A fourteenth aspect A14 includes the colored article according to anyone of the first through thirteenth aspects A1-A13, wherein the coloredglass article comprises greater than or equal to 0.01 mol % and lessthan or equal to 1 mol % Fe₂O₃.

A fifteenth aspect A15 includes the colored article according to thefourteenth aspect A14, wherein the colored glass article comprisesgreater than or equal to 0.05 mol % and less than or equal to 0.5 mol %Fe₂O₃.

A sixteenth aspect A16 includes the colored article according to any oneof the first through fifteenth aspects A1-A15, wherein 5.72*Al₂O₃ (mol%)−21.4*ZnO (mol %)−2.5*P₂O₅ (mol %)−35*Li₂O (mol %)−16.6*B₂O₃ (mol%)−20.5*MgO (mol %)−23.3*Na₂O (mol %)−27.9*SrO (mol %)−18.5*K₂O (mol%)−26.3*CaO (mol %) is greater than −609 mol %.

A seventeenth aspect A17 includes the colored glass article according toany one of the first through sixteenth aspects A1-A16, wherein thecolored glass article comprises greater than or equal to 0.01 mol % andless than or equal to 1 mol % SnO₂.

An eighteenth aspect A18 includes the colored glass article according tothe seventeenth aspect A17, wherein the colored glass article comprisesgreater than or equal to 0.05 mol % and less than or equal to 0.75 mol %SnO₂.

A nineteenth aspect A19 includes the colored glass article according toany one of the first through eighteenth aspects A1-A18, wherein thecolored glass article is substantially free of MgO, CaO, ZnO, Cl, orcombinations thereof.

A twentieth aspect A20 includes the colored glass article according toany one of the first through nineteenth aspects A1-A19, wherein thecolored glass article comprises greater than or equal to 7 mol % andless than or equal to 18 mol % Li₂O.

A twenty-first aspect A21 includes the colored glass article accordingto the twentieth aspect A20, wherein the colored glass article comprisesgreater than or equal to 9 mol % and less than or equal to 16 mol %Li₂O.

A twenty-second aspect A22 includes the colored glass article accordingto any one of the first through twenty-first aspects A1-A21, wherein thecolored glass article comprises greater than or equal to 1 mol % andless than or equal to 12 mol % Na₂O.

A twenty-third aspect A23 includes the colored glass article accordingto the twenty-second aspect A22, wherein the colored glass articlecomprises greater than or equal to 2 mol % and less than or equal to 10mol % Na₂O.

A twenty-forth aspect A24 includes the colored glass article accordingto any one of the first through twenty-third aspects A1-A23, wherein thecolored glass article comprises greater than or equal to 0.1 mol % andless than or equal to 0.5 mol % K₂O.

A twenty-fifth aspect A25 includes the colored glass article accordingto any one of the first through twenty-fourth aspects A1-A24, whereinthe colored glass article comprises greater than or equal to 9 mol % andless than or equal to 23 mol % Al₂O₃.

A twenty-sixth aspect A26 includes the colored glass article accordingto the twenty-fifth aspect A25, wherein the colored glass articlecomprises greater than or equal to 11 mol % and less than or equal to 20mol % Al₂O₃.

A twenty-seventh aspect A27 includes the colored glass article accordingto any one of the first through twenty-sixth aspects A1-A26, wherein thecolored glass article comprises greater than or equal to 2 mol % andless than or equal to 12 mol % B₂O₃.

A twenty-eighth aspect A28 includes the colored glass article accordingto the twenty-seventh aspect A27, wherein the colored glass articlecomprises greater than or equal to 3 mol % and less than or equal to 10mol % B₂O₃.

A twenty-ninth aspect A29 includes the colored glass article accordingto any one of the first through twenty-eighth aspects A1-A28, whereinthe colored glass article comprises greater than or equal to 52 mol %and less than or equal to 75 mol % SiO₂.

A thirtieth aspect A30 includes the colored glass article according toany one of the first through twenty-ninth aspects A1-A29, wherein thecolored glass article has a thickness greater than or equal to 250 μmand less than or equal to 6 mm.

A thirty-first aspect A31 includes the colored glass article accordingto any one of the first through thirtieth aspects A1-A30, wherein thecolored glass article is an ion-exchanged colored glass article.

A thirty-second aspect A32 includes the colored glass article accordingto the thirty-first aspect A31, wherein the ion-exchanged colored glassarticle has a depth of compression 10 μm or greater.

A thirty-third aspect A33 includes the colored glass article accordingto the thirty-first aspect A31 or thirty-second aspect A32, wherein theion-exchanged colored glass article has a thickness “t” and a depth ofcompression greater than or equal to 0.15 t.

A thirty-fourth aspect A34 includes the colored glass article accordingto any one of the thirty-first through thirty-third aspects A31-A33,wherein the ion-exchanged colored glass article has a surfacecompressive stress greater than or equal to 300 MPa.

A thirty-fifth aspect A35 includes the colored glass article accordingto any one of the thirty-first through thirty-fourth aspects A31-A34,wherein the ion-exchanged colored glass article has a maximum centraltension greater than or equal to 40 MPa.

According to a thirty-sixth aspect A36, a consumer electronic device maycomprise: a housing having a front surface, a back surface, and sidesurfaces; and electrical components provided at least partially withinthe housing, the electrical components including at least a controller,a memory, and a display, the display being provided at or adjacent thefront surface of the housing; wherein the housing comprises the coloredglass article according to any one of the first through thirty-fifthaspects A1-A35.

According to a thirty-seventh aspect A37, a glass composition maycomprise: greater than or equal to 50 mol % and less than or equal to 80mol % SiO₂; greater than or equal to 7 mol % and less than or equal to25 mol % Al₂O₃; greater than or equal to 1 mol % and less than or equalto 15 mol % B₂O₃; greater than or equal to 5 mol % and less than orequal to 20 mol % Li₂O; greater than or equal to 0.5 mol % and less thanor equal to 15 mol % Na₂O; greater than 0 mol % and less than or equalto 1 mol % K₂O; and greater than or equal to 1×10⁻⁶ mol % and less thanor equal to 1 mol % Au, wherein: R₂O—Al₂O₃ is greater than or equal to−5 mol % and less than or equal to 7 mol %, R₂O being the sum of Li₂O,Na₂O, and K₂O.

A thirty-eighth aspect A38 includes the glass composition according tothe thirty-seventh aspect A37, wherein R₂O—Al₂O₃ is greater than orequal to −3 mol % and less than or equal to 5 mol %.

A thirty-ninth aspect A39 includes the glass composition according tothe thirty-eighth aspect A38, wherein R₂O—Al₂O₃ is greater than or equalto −1 mol % and less than or equal to 3 mol %.

A fortieth aspect A40 includes the glass compositions according to thethirty-seventh through thirty-ninth aspects A37-A39, wherein the glasscomposition comprises greater than or equal to 0.0001 mol % and lessthan or equal to 0.1 mol % Au.

A forty-first aspect A41 includes the glass composition according to anyone of the thirty-seventh through fortieth aspects A37-A40, wherein R₂Ois greater than or equal to 6 mol % and less than or equal to 25 mol %.

A forty-second aspect A42 includes the glass composition according tothe forty-first aspect A41, wherein R₂O is greater than or equal to 8mol % and less than or equal to 23 mol %.

A forty-third aspect A43 includes the glass composition according to anyone of the thirty-seventh through forty-second aspects A37-A42, whereinthe glass composition comprises greater than or equal to 0.01 mol % andless than or equal to 2 mol % ZrO₂.

A forty-fourth aspect A44 includes the glass composition of theforty-third aspect A43, wherein the glass composition comprises greaterthan or equal to 0.1 mol % and less than or equal to 1.5 mol % ZrO₂.

A forty-fifth aspect A45 includes the glass composition of any one ofthe thirty-seventh through forty-fourth aspects A37-A44, wherein theglass composition comprises greater than or equal to 0.01 mol % and lessthan or equal to 1 mol % Fe₂O₃.

A forty-sixth aspect A46 includes the glass composition according to theforty-fifth aspect A45, wherein the glass composition comprises greaterthan or equal to 0.05 mol % and less than or equal to 0.5 mol % Fe₂O₃.

A forty-seventh aspect A47 includes the glass composition according toany one of the thirty-seventh through forty-sixth aspects A37-A46,wherein 5.72*Al₂O₃ (mol %)−21.4*ZnO (mol %)−2.5*P₂O₅ (mol %)−35*Li₂O(mol %)−16.6*B₂O₃ (mol %)−20.5*MgO (mol %)−23.3*Na₂O (mol %)−27.9*SrO(mol %)−18.5*K₂O (mol %)−26.3*CaO (mol %) is greater than −609 mol %.

A forty-eighth aspect A48 includes the glass composition according toany one of the thirty-seventh through forty-seventh aspects A37-A47,wherein the glass composition comprises greater than or equal to 0.01mol % and less than or equal to 1 mol % SnO₂.

A forty-ninth aspect A49 includes the glass composition according to theforty-eighth aspect A48, wherein the glass composition comprises greaterthan or equal to 0.05 mol % and less than or equal to 0.75 mol % SnO₂.

A fiftieth aspect A50 includes the glass composition according to anyone of the thirty-seventh through forty-ninth aspects A37-A49, whereinthe glass composition is substantially free of MgO, CaO, ZnO, Cl, orcombinations thereof.

A fifty-first aspect A51 includes the glass composition according to anyone of the thirty-seventh through fiftieth aspects A37-A50, wherein theglass composition comprises greater than or equal to 7 mol % and lessthan or equal to 18 mol % Li₂O.

A fifty-second aspect A52 includes the glass composition according tothe fifty-first aspect A51, wherein the glass composition comprisesgreater than or equal to 9 mol % and less than or equal to 16 mol %Li₂O.

A fifty-third aspect A53 includes the glass composition according to anyone of the thirty-seventh through fifty-second aspects A37-A52, whereinthe glass composition comprises greater than or equal to 1 mol % andless than or equal to 12 mol % Na₂O.

A fifty-fourth aspect A54 includes the glass composition according tothe fifty-third aspect A53, wherein the glass composition comprisesgreater than or equal to 2 mol % and less than or equal to 10 mol %Na₂O.

A fifty-fifth aspect A55 includes the glass composition according to anyone of the thirty-seventh through fifty-fourth aspects A37-A54, whereinthe glass composition comprises greater than or equal to 0.1 mol % andless than or equal to 0.5 mol % K₂O.

A fifty-sixth aspect A56 includes the glass composition according to anyone of the thirty-seventh through fifty-fifth aspects A37-A55, whereinthe glass composition comprises greater than or equal to 9 mol % andless than or equal to 23 mol % Al₂O₃.

A fifty-seventh aspect A57 includes the glass composition according tothe fifty-sixth aspect A56, wherein the glass composition comprisesgreater than or equal to 11 mol % and less than or equal to 20 mol %Al₂O₃.

A fifty-eighth aspect A58 includes the glass composition according toany one of the thirty-seventh through fifty-seventh aspect A37-A57,wherein the glass composition comprises greater than or equal to 2 mol %and less than or equal to 12 mol % B₂O₃.

A fifty-ninth aspect A59 includes the glass composition according to thefifty-eighth aspect A58, wherein the glass composition comprises greaterthan or equal to 3 mol % and less than or equal to 10 mol % B₂O₃.

A sixtieth aspect A60 includes the glass composition according to anyone of the thirty-seventh through fifty-ninth aspects A37-A59, whereinthe glass composition comprises greater than or equal to 52 mol % andless than or equal to 75 mol % SiO₂.

According to a sixty-first aspect A61, a method of forming a coloredglass article may comprise: heat treating a glass composition to form aglass article, the glass composition comprising: greater than or equalto 50 mol % and less than or equal to 80 mol % SiO₂; greater than orequal to 7 mol % and less than or equal to 25 mol % Al₂O₃; greater thanor equal to 1 mol % and less than or equal to 15 mol % B₂O₃; greaterthan or equal to 5 mol % and less than or equal to 20 mol % Li₂O;greater than or equal to 0.5 mol % and less than or equal to 15 mol %Na₂O; greater than 0 mol % and less than or equal to 1 mol % K₂O; andgreater than or equal to 1×10⁻⁶ mol % and less than or equal to 1 mol %Au, wherein: R₂O—Al₂O₃ is greater than or equal to −5 mol % and lessthan or equal to 7 mol %, R₂O being the sum of Li₂O, Na₂O, and K₂O; andsubjecting the glass article to a heat treatment cycle at a temperaturegreater than or equal to 500° C. and less than or equal to 800° C. and aduration greater than or equal to 0.25 hour and less than or equal to 24hours to produce the colored glass article.

A sixty-second aspect A62 includes the method according to thesixty-first aspect A61, wherein the temperature of the heat treatmentcycle is greater than or equal to 550° C. and less than or equal to 775°C.

A sixty-third aspect A63 includes the method according to thesixty-first aspect A61 or sixty-second aspect A62, wherein the durationof the heat treatment cycle is greater than or equal to 0.5 hour andless than or equal to 16 hours.

A sixty-fourth aspect A64 includes the method according to any one ofthe sixty-first through sixty-third aspects A61-A63, further comprisingstrengthening the colored glass article in an ion exchange bath at atemperature greater than or equal to 350° C. to less than or equal to500° C. for a time period greater than or equal to 2 hours to less thanor equal to 12 hours to form an ion exchanged glass-ceramic article.

A sixty-fifth aspect A65 includes the method according to thesixty-fourth aspect A64, wherein the ion exchange bath comprises KNO₃.

A sixty-sixth aspect A66 includes the method according to thesixty-fifth aspect A65, wherein the ion exchange bath comprises NaNO₃.

Additional features and advantages of the colored glass articlesdescribed herein will be set forth in the detailed description whichfollows, and in part will be readily apparent to those skilled in theart from that description or recognized by practicing the embodimentsdescribed herein, including the detailed description which follows, theclaims, as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description describe various embodiments and areintended to provide an overview or framework for understanding thenature and character of the claimed subject matter. The accompanyingdrawings are included to provide a further understanding of the variousembodiments, and are incorporated into and constitute a part of thisspecification. The drawings illustrate the various embodiments describedherein, and together with the description serve to explain theprinciples and operations of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an electronic device incorporating any of thecolored glass articles according to one or more embodiments describedherein;

FIG. 2 is a perspective view of the electronic device of FIG. 1 ;

FIG. 3 is a plot of R₂O—Al₂O₃ vs. a* CIELAB space (x-axis: R₂O—Al₂O₃;y-axis: a*) of colored glass articles made from glass compositions andsubjected to a heat treatment according to one or more embodimentsdescribed herein; and

FIG. 4 is a plot of R₂O—Al₂O₃ vs. b* CIELAB space (x-axis: R₂O—Al₂O₃;y-axis: b*) of colored glass articles made from glass compositions andsubjected to a heat treatment according to one or more embodimentsdescribed herein.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of glasscompositions and colored glass articles formed therefrom having adesired color. According to embodiments, a colored glass articleincludes greater than or equal to 50 mol % and less than or equal to 80mol % SiO₂; greater than or equal to 7 mol % and less than or equal to25 mol % Al₂O₃; greater than or equal to 1 mol % and less than or equalto 15 mol % B₂O₃; greater than or equal to 5 mol % and less than orequal to 20 mol % Li₂O; greater than or equal to 0.5 mol % and less thanor equal to 15 mol % Na₂O; greater than 0 mol % and less than or equalto 1 mol % K₂O; and greater than or equal to 1×10⁻⁶ mol % and less thanor equal to 1 mol % Au. R₂O—Al₂O₃ is greater than or equal to −5 mol %and less than or equal to 7 mol %, R₂O being the sum of Li₂O, Na₂O, andK₂O.

Various embodiments of colored glass articles and methods of making thesame will be described herein with specific reference to the appendeddrawings.

Ranges may be expressed herein as from “about” one particular value,and/or to “about” another particular value. When such a range isexpressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment. Itwill be further understood that the endpoints of each of the ranges aresignificant both in relation to the other endpoint, and independently ofthe other endpoint.

Directional terms as used herein—for example up, down, right, left,front, back, top, bottom—are made only with reference to the figures asdrawn and are not intended to imply absolute orientation.

Unless otherwise expressly stated, it is in no way intended that anymethod set forth herein be construed as requiring that its steps beperformed in a specific order, nor that with any apparatus specificorientations be required. Accordingly, where a method claim does notactually recite an order to be followed by its steps, or that anyapparatus claim does not actually recite an order or orientation toindividual components, or it is not otherwise specifically stated in theclaims or description that the steps are to be limited to a specificorder, or that a specific order or orientation to components of anapparatus is not recited, it is in no way intended that an order ororientation be inferred, in any respect. This holds for any possiblenon-express basis for interpretation, including: matters of logic withrespect to arrangement of steps, operational flow, order of components,or orientation of components; plain meaning derived from grammaticalorganization or punctuation, and; the number or type of embodimentsdescribed in the specification.

As used herein, the singular forms “a,” “an” and “the” include pluralreferents unless the context clearly dictates otherwise. Thus, forexample, reference to “a” component includes aspects having two or moresuch components, unless the context clearly indicates otherwise.

In the embodiments of the glass compositions and the resultant coloredglass articles described herein, the concentrations of constituentcomponents in oxide form (e.g., SiO₂, Al₂O₃, and the like) are specifiedin mole percent (mol %) on an oxide basis, unless otherwise specified.

In embodiments of the glass compositions and the resultant colored glassarticles described herein, the concentration of Au and Cl is specifiedin mole percent (mol %), unless otherwise specified.

The term “substantially free,” when used to describe the concentrationand/or absence of a particular constituent component in a glasscomposition and the resultant colored glass article, means that theconstituent component is not intentionally added to the glasscomposition and the resultant colored glass article. However, the glasscomposition and the resultant colored glass article may contain tracesof the constituent component as a contaminant or tramp in amounts ofless than 0.1 mol %.

The terms “0 mol %” and “free,” when used to describe the concentrationand/or absence of a particular constituent component in a glasscomposition and the resultant colored glass article, means that theconstituent component is not present in glass composition and theresultant colored glass article.

Fracture toughness (K_(1C)) represents the ability of a glasscomposition to resist fracture. Fracture toughness is measured on anon-strengthened glass article, such as measuring the K_(1C) value priorto ion exchange (IOX) treatment of the glass article, therebyrepresenting a feature of a glass substrate prior to IOX. The fracturetoughness test methods described herein are not suitable for glassesthat have been exposed to IOX treatment. But, fracture toughnessmeasurements performed as described herein on the same glass prior toIOX treatment (e.g., glass substrates) correlate to fracture toughnessafter IOX treatment, and are accordingly used as such. The chevronnotched short bar (CNSB) method utilized to measure the K_(1C) value isdisclosed in Reddy, K. P. R. et al, “Fracture Toughness Measurement ofGlass and Ceramic Materials Using Chevron-Notched Specimens,” J. Am.Ceram. Soc., 71 [6], C-310-C-313 (1988) except that Y*m is calculatedusing equation 5 of Bubsey, R. T. et al., “Closed-Form Expressions forCrack-Mouth Displacement and Stress Intensity Factors forChevron-Notched Short Bar and Short Rod Specimens Based on ExperimentalCompliance Measurements,” NASA Technical Memorandum 83796, pp. 1-30(October 1992). Unless otherwise specified, all fracture toughnessvalues were measured by chevron notched short bar (CNSB) method.

The term “liquidus viscosity,” as used herein, refers to the viscosityof the glass composition at the onset of devitrification (i.e., at theliquidus temperature as determined with the gradient furnace methodaccording to ASTM C829-81).

Surface compressive stress is measured with a surface stress meter (FSM)such as commercially available instruments such as the FSM-6000,manufactured by Orihara Industrial Co., Ltd. (Japan). Surface stressmeasurements rely upon the measurement of the stress optical coefficient(SOC), which is related to the birefringence of the glass article. SOC,in turn, is measured according to Procedure C (Glass Disc Method)described in ASTM standard C770-16, entitled “Standard Test Method forMeasurement of Glass Stress-Optical Coefficient,” the contents of whichare incorporated herein by reference in their entirety. Depth ofcompression (DOC) is also measured with the FSM. The maximum centraltension (CT) values are measured using a scattered light polariscope(SCALP) technique known in the art.

The term “depth of compression” (DOC), as used herein, refers to theposition in the article where compressive stress transitions to tensilestress.

The term “CIELAB color space,” as used herein, refers to a color spacedefined by the International Commission on Illumination (CIE) in 1976.It expresses color as three values: L* for the lightness from black (0)to white (100), a* from green (−) to red (+), and B* from blue (−) toyellow (+).

The term “color gamut,” as used herein, refers to the pallet of colorsthat may be achieved by the colored glass articles within the CIELABcolor space.

The “optical transmission spectra,” as used herein, were obtained usingan Agilent Cary 60 spectrophotometer with a scan range of 250 nm to 800nm, a scan step of 2 nm, a signal average of 0.5 s, and a spot size of 2mm. The optical transmission data obtained were used to plot coordinatesin the CIELAB color space as described in R. S. Berns, Billmeyer andSaltzman's Principles of Color Technology, 3rd. Ed., John Wiley & Sons,New York (2000).

Colorants have been added to conventional aluminosilicate glasscompositions to achieve a colored glass article having a desired colorand improved mechanical properties. For example, gold (Au) doped glassarticles generally appear red, orange, or purple. However, simplyincluding colorants in aluminosilicate glass compositions may notproduce the desired color.

Disclosed herein are glass compositions and colored glass articlesformed therefrom that mitigate the aforementioned problems such that Aumay be added to aluminosilicate glass compositions to produce coloredglass articles having the desired color while retaining superiorion-exchange and drop performance. Specifically, the concentration ofcertain constituent components may be adjusted to achieve a desiredcolor and to prevent precipitation of Au particles in the glass network.

The glass compositions and colored glass articles described herein maybe described as aluminoborosilicate glass compositions and colored glassarticles and comprise SiO₂, Al₂O₃, and B₂O₃. In addition to SiO₂, Al₂O₃,and B₂O₃, the glass compositions and colored glass articles describedherein include Auto produce colored glass articles having the desiredcolor. The glass compositions and colored glass articles describedherein also include alkali oxides, such as Li₂O and Na₂O, to enable theion-exchangeability of the colored glass articles. Additionally, thedifference of R₂O and Al₂O₃ (i.e. R₂O (mol %)−Al₂O₃ (mol %)) in theglass compositions and resultant colored glass articles described hereinmay be adjusted to produce a desired observable color (e.g., pink,purple, red, or orange). Furthermore, the viscosity of the glasscomposition may be adjusted to prevent devitrification of the glasscomposition and precipitation of Au particles during melting and formingthat may limit the color gamut that may be achieved.

SiO₂ is the primary glass former in the glass compositions describedherein and may function to stabilize the network structure of thecolored glass articles. The concentration of SiO₂ in the glasscompositions and resultant colored glass articles should be sufficientlyhigh (e.g., greater than or equal to 50 mol %) to enhance the chemicaldurability of the glass composition and, in particular, the resistanceof the glass composition to degradation upon exposure to acidicsolutions, basic solutions, and in water. The amount of SiO₂ may belimited (e.g., to less than or equal to 80 mol %) to control the meltingpoint of the glass composition, as the melting point of pure SiO₂ orhigh SiO₂ glasses is undesirably high. Thus, limiting the concentrationof SiO₂ may aid in improving the meltability and the formability of theresultant colored glass article.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 50 mol % and less than orequal to 80 mol % SiO₂. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to 52mol % and less than or equal to 75 mol % SiO₂. In embodiments, theconcentration of SiO₂ in the glass composition and the resultant coloredglass article may be greater than or equal to 50 mol %, greater than orequal to 52 mol %, greater than or equal to 54 mol %, greater than orequal to 56 mol %, greater than or equal to 58 mol %, or even greaterthan or equal to 60 mol %. In embodiments, the concentration of SiO₂ inthe glass composition and the colored resultant glass article may beless than or equal to 80 mol %, less than or equal to 75 mol %, lessthan or equal to 73 mol %, less than or equal to 71 mol %, or even lessthan or equal to 69 mol %. In embodiments, the concentration of SiO₂ inthe glass composition and the resultant colored glass article may begreater than or equal to 50 mol % and less than or equal to 80 mol %,greater than or equal to 50 mol % and less than or equal to 75 mol %,greater than or equal to 50 mol % and less than or equal to 73 mol %,greater than or equal to 50 mol % and less than or equal to 71 mol %,greater than or equal to 50 mol % and less than or equal to 69 mol %,greater than or equal to 52 mol % and less than or equal to 80 mol %,greater than or equal to 52 mol % and less than or equal to 75 mol %,greater than or equal to 52 mol % and less than or equal to 73 mol %,greater than or equal to 52 mol % and less than or equal to 71 mol %,greater than or equal to 52 mol % and less than or equal to 69 mol %,greater than or equal to 54 mol % and less than or equal to 80 mol %,greater than or equal to 54 mol % and less than or equal to 75 mol %,greater than or equal to 54 mol % and less than or equal to 73 mol %,greater than or equal to 54 mol % and less than or equal to 71 mol %,greater than or equal to 54 mol % and less than or equal to 69 mol %,greater than or equal to 56 mol % and less than or equal to 80 mol %,greater than or equal to 56 mol % and less than or equal to 75 mol %,greater than or equal to 56 mol % and less than or equal to 73 mol %,greater than or equal to 56 mol % and less than or equal to 71 mol %,greater than or equal to 56 mol % and less than or equal to 69 mol %,greater than or equal to 58 mol % and less than or equal to 80 mol %,greater than or equal to 58 mol % and less than or equal to 75 mol %,greater than or equal to 58 mol % and less than or equal to 73 mol %,greater than or equal to 58 mol % and less than or equal to 71 mol %,greater than or equal to 58 mol % and less than or equal to 69 mol %,greater than or equal to 50 mol % and less than or equal to 80 mol %,greater than or equal to 60 mol % and less than or equal to 75 mol %,greater than or equal to 60 mol % and less than or equal to 73 mol %,greater than or equal to 60 mol % and less than or equal to 71 mol %, oreven greater than or equal to 60 mol % and less than or equal to 69 mol%, or any and all sub-ranges formed from any of these endpoints.

Like SiO₂, Al₂O₃ may also stabilize the glass network and additionallyprovides improved mechanical properties and chemical durability to theglass composition and the resultant colored glass article. The amount ofAl₂O₃ may also be tailored to control the viscosity of the glasscomposition. Al₂O₃ may be included such that the resultant glasscomposition has the desired fracture toughness (e.g., greater than orequal to 0.7 MPa·m^(1/2)). However, if the amount of Al₂O₃ is too high(e.g., greater than 25 mol %), the viscosity of the glass melt mayincrease, thereby diminishing the formability of the colored glassarticle.

Accordingly, in embodiments, the glass composition and the resultantcolored glass article may comprise greater than or equal to 7 mol % andless than or equal to 25 mol % Al₂O₃. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 9 mol % and less than or equal to 23 mol % Al₂O₃. Inembodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 11 mol % and less than orequal to 20 mol % Al₂O₃. In embodiments, the concentration of Al₂O₃ inthe glass composition and the resultant colored glass article may begreater than or equal to 7 mol %, greater than or equal to 9 mol %,greater than or equal to 11 mol %, or even greater than or equal to 13mol %. In embodiments, the concentration of Al₂O₃ in the glasscomposition and the resultant colored glass article may be less than orequal to 25 mol %, less than or equal to 23 mol %, less than or equal to20 mol %, or even less than or equal to 17 mol %. In embodiments, theconcentration of Al₂O₃ in the glass composition and the resultantcolored glass article may be greater than or equal to 7 mol % and lessthan or equal to 25 mol %, greater than or equal to 7 mol % and lessthan or equal to 23 mol %, greater than or equal to 7 mol % and lessthan or equal to 20 mol %, greater than or equal to 7 mol % and lessthan or equal to 17 mol %, greater than or equal to 9 mol % and lessthan or equal to 25 mol %, greater than or equal to 9 mol % and lessthan or equal to 23 mol %, greater than or equal to 9 mol % and lessthan or equal to 20 mol %, greater than or equal to 9 mol % and lessthan or equal to 17 mol %, greater than or equal to 11 mol % and lessthan or equal to 25 mol %, greater than or equal to 11 mol % and lessthan or equal to 23 mol %, greater than or equal to 11 mol % and lessthan or equal to 20 mol %, greater than or equal to 11 mol % and lessthan or equal to 17 mol %, greater than or equal to 13 mol % and lessthan or equal to 25 mol %, greater than or equal to 13 mol % and lessthan or equal to 23 mol %, greater than or equal to 13 mol % and lessthan or equal to 20 mol %, greater than or equal to 13 mol % and lessthan or equal to 17 mol %, or any and all sub-ranges formed from any ofthese endpoints.

B₂O₃ helps improve the damage resistance of the resultant colored glassarticle. In addition, B₂O₃ reduces the formation of non-bridging oxygen,the presence of which may reduce fracture toughness. The concentrationof B₂O₃ should be sufficiently high (e.g., greater than or equal to 1mol %) to reduce the melting point of the glass composition, improve theformability, and increase the fracture toughness of the colored glassarticle. However, if B₂O₃ is too high (e.g., greater than 15 mol %), theannealing point and strain point may decrease, which increases stressrelaxation and reduces the overall strength of the colored glassarticle.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 1 mol % and less than orequal to 15 mol % B₂O₃. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to 2mol % and less than or equal to 12 mol % B₂O₃. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 3 mol % and less than or equal to 10 mol % B₂O₃. Inembodiments, the concentration of B₂O₃ in the glass composition and theresultant colored glass article may be greater than or equal to 1 mol %,greater than or equal to 2 mol %, greater than or equal to 3 mol %, oreven greater than or equal to 4 mol %. In embodiments, the concentrationof B₂O₃ in the glass composition and the resultant colored glass articlemay be less than or equal to 15 mol %, less than or equal to 12 mol %,less than or equal to 10 mol %, less than or equal to 8 mol %, or evenless than or equal to 6 mol %. In embodiments, the concentration of B₂O₃in the glass composition and the resultant colored glass article may begreater than or equal to 1 mol % and less than or equal to 15 mol %,greater than or equal to 1 mol % and less than or equal to 12 mol %,greater than or equal to 1 mol % and less than or equal to 10 mol %,greater than or equal to 1 mol % and less than or equal to 8 mol %,greater than or equal to 1 mol % and less than or equal to 6 mol %,greater than or equal to 2 mol % and less than or equal to 15 mol %,greater than or equal to 2 mol % and less than or equal to 12 mol %,greater than or equal to 2 mol % and less than or equal to 10 mol %,greater than or equal to 2 mol % and less than or equal to 8 mol %,greater than or equal to 2 mol % and less than or equal to 6 mol %,greater than or equal to 3 mol % and less than or equal to 15 mol %,greater than or equal to 3 mol % and less than or equal to 12 mol %,greater than or equal to 3 mol % and less than or equal to 10 mol %,greater than or equal to 3 mol % and less than or equal to 8 mol %,greater than or equal to 3 mol % and less than or equal to 6 mol %,greater than or equal to 4 mol % and less than or equal to 15 mol %,greater than or equal to 4 mol % and less than or equal to 12 mol %,greater than or equal to 4 mol % and less than or equal to 10 mol %,greater than or equal to 4 mol % and less than or equal to 8 mol %, oreven greater than or equal to 4 mol % and less than or equal to 6 mol %,or any and all sub-ranges formed from any of these endpoints.

As described hereinabove, the glass compositions and the resultantcolored glass articles may contain alkali oxides, such as Li₂O, Na₂O,and K₂O, to enable the ion-exchangeability of the colored glassarticles.

Li₂O aids in the ion-exchangeability of the colored glass article andalso reduces the softening point of the glass composition, therebyincreasing the formability of the colored glass articles. In addition,Li₂O decreases the melting point of the glass composition, which mayhelp improve Au retention. The concentration of Li₂O in the glasscompositions and resultant colored glass articles should be sufficientlyhigh (e.g., greater than or equal to 5 mol %) to reduce the meltingpoint of the glass composition and achieve the desired maximum centraltension (e.g., greater than or equal to 40 MPa) following ion-exchange.However, if the amount of Li₂O is too high (e.g., greater than 20 mol%), the liquidus temperature may increase, thereby diminishing themanufacturability of the colored glass article.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 5 mol % and less than orequal to 20 mol % Li₂O. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to 7mol % and less than or equal to 18 mol % Li₂O. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 9 mol % and less than or equal to 16 mol % Li₂O. Inembodiments, the concentration of Li₂O in the glass composition and theresultant colored glass article may be greater than or equal to 5 mol %,greater than or equal to 7 mol %, or even greater than or equal to 9 mol%. In embodiments, the concentration of Li₂O in the glass compositionand the resultant colored glass article may be less than or equal to 20mol %, less than or equal to 18 mol %, less than or equal to 16 mol %,less than or equal to 14 mol %, or even less than or equal to 12 mol %.In embodiments, the concentration of Li₂O in the glass composition andthe resultant colored glass article may be greater than or equal to 5mol % and less than or equal to 20 mol %, greater than or equal to 5 mol% and less than or equal to 18 mol %, greater than or equal to 5 mol %and less than or equal to 16 mol %, greater than or equal to 5 mol % andless than or equal to 14 mol %, greater than or equal to 5 mol % andless than or equal to 12 mol %, greater than or equal to 7 mol % andless than or equal to 20 mol %, greater than or equal to 7 mol % andless than or equal to 18 mol %, greater than or equal to 7 mol % andless than or equal to 16 mol %, greater than or equal to 7 mol % andless than or equal to 14 mol %, greater than or equal to 7 mol % andless than or equal to 12 mol %, greater than or equal to 9 mol % andless than or equal to 20 mol %, greater than or equal to 9 mol % andless than or equal to 18 mol %, greater than or equal to 9 mol % andless than or equal to 16 mol %, greater than or equal to 9 mol % andless than or equal to 14 mol %, or even greater than or equal to 9 mol %and less than or equal to 12 mol %, or any and all sub-ranges formedfrom any of these endpoints.

Na₂O improves diffusivity of alkali ions in the glass and therebyreduces ion-exchange time and helps achieve the desired surfacecompressive stress (e.g., greater than or equal to 300 MPa). Na₂O alsoimproves the formability of the colored glass article. However, if toomuch Na₂O is added to the glass composition, the melting point may betoo low. As such, in embodiments, the concentration of Li₂O present inthe glass composition and the resultant colored glass article may begreater than the concentration of Na₂O present in the glass compositionand the resultant colored glass article.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 0.5 mol % and less than orequal to 15 mol % Na₂O. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to 1mol % and less than or equal to 12 mol % Na₂O. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 2 mol % and less than or equal to 10 mol % Na₂O. Inembodiments, the concentration of Na₂O in the glass composition and theresultant colored glass article may be greater than or equal to 0.5 mol%, greater than or equal to 1 mol %, greater than or equal to 2 mol %,greater than or equal to 3 mol %, or even greater than or equal to 4 mol%. In embodiments, the concentration of Na₂O in the glass compositionand the resultant colored glass article may be less than or equal to 15mol %, less than or equal to 12 mol %, less than or equal to 10 mol %,less than or equal to 8 mol %, or even less than or equal to 6 mol %. Inembodiments, the concentration of Na₂O in the glass composition and theresultant colored glass article may be greater than or equal to 0.5 mol% and less than or equal to 15 mol %, greater than or equal to 0.5 mol %and less than or equal to 12 mol %, greater than or equal to 0.5 mol %and less than or equal to 10 mol %, greater than or equal to 0.5 mol %and less than or equal to 8 mol %, greater than or equal to 0.5 mol %and less than or equal to 6 mol %, greater than or equal to 1 mol % andless than or equal to 15 mol %, greater than or equal to 1 mol % andless than or equal to 12 mol %, greater than or equal to 1 mol % andless than or equal to 10 mol %, greater than or equal to 1 mol % andless than or equal to 8 mol %, greater than or equal to 1 mol % and lessthan or equal to 6 mol %, greater than or equal to 2 mol % and less thanor equal to 15 mol %, greater than or equal to 2 mol % and less than orequal to 12 mol %, greater than or equal to 2 mol % and less than orequal to 10 mol %, greater than or equal to 2 mol % and less than orequal to 8 mol %, greater than or equal to 2 mol % and less than orequal to 6 mol %, greater than or equal to 3 mol % and less than orequal to 15 mol %, greater than or equal to 3 mol % and less than orequal to 12 mol %, greater than or equal to 3 mol % and less than orequal to 10 mol %, greater than or equal to 3 mol % and less than orequal to 8 mol %, greater than or equal to 3 mol % and less than orequal to 6 mol %, greater than or equal to 4 mol % and less than orequal to 15 mol %, greater than or equal to 4 mol % and less than orequal to 12 mol %, greater than or equal to 4 mol % and less than orequal to 10 mol %, greater than or equal to 4 mol % and less than orequal to 8 mol %, or even greater than or equal to 4 mol % and less thanor equal to 6 mol %, or any and all sub-ranges formed from any of theseendpoints.

K₂O promotes ion-exchange and may increase the depth of compression anddecrease the melting point to improve the formability of the coloredglass article. However, adding too much K₂O may cause the surfacecompressive stress and melting point to be too low. Accordingly, inembodiments, the amount of K₂O added to the glass composition may belimited.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than 0 mol % and less than or equal to 1mol % K₂O. In embodiments, the glass composition and the resultantcolored glass article may optionally comprise greater than 0.1 mol % andless than or equal to 0.5 mol % K₂O. In embodiments, the concentrationof K₂O in the glass composition and the resultant colored glass articlemay be greater than 0 mol % or even greater than or equal to 0.1 mol %.In embodiments, the concentration of K₂O in the glass composition andthe resultant colored glass article may be less than or equal to 1 mol%, less than or equal to 0.5 mol %, or even less than or equal to 0.25mol %. In embodiments, the concentration of K₂O in the glass compositionand the resultant colored glass article may be greater than 0 mol % andless than or equal to 1 mol %, greater than 0 mol % and less than orequal to 0.5 mol %, greater than 0 mol % and less than or equal to 0.25mol %, greater than or equal to 0.1 mol % and less than or equal to 1mol %, greater than or equal to 0.1 mol % and less than or equal to 0.5mol %, or even greater than or equal to 0.1 mol % and less than or equalto 0.25 mol %, or any and all sub-ranges formed from any of theseendpoints.

As used herein, R₂O is the sum (in mol %) of Na₂O, K₂O, and Li₂O (i.e.,R₂O=Na₂O (mol %)+K₂O (mol %)+Li₂O (mol %)) present in the glasscomposition. As noted herein, alkali oxides, such as Na₂O, K₂O, andLi₂O, aid in decreasing the softening point and molding temperature ofthe glass composition, thereby offsetting the increase in the softeningpoint and molding temperature of the glass composition due to higheramounts of SiO₂ in the glass composition, for example. The decrease inthe softening point and molding temperature may be further reduced byincluding combinations of alkali oxides (e.g., two or more alkalioxides) in the glass composition, a phenomenon referred to as the “mixedalkali effect.” However, it has been found that if the amount of alkalioxide is too high, the average coefficient of thermal expansion of theglass composition increases to greater than 100×10⁷/° C., which may beundesirable.

In embodiments, the concentration of R₂O in the glass composition andthe resultant colored glass article may be greater than or equal to 6mol % and less than or equal to 25 mol %. In embodiments, theconcentration of R₂O in the glass composition and the resultant coloredglass article may be greater than or equal to 8 mol % and less than orequal to 23 mol %. In embodiments, the concentration of R₂O in the glasscomposition and the resultant colored glass article may be greater thanor equal to 6 mol %, greater than or equal to 8 mol %, greater than 10mol %, greater than or equal to 12 mol %, or even greater than or equalto 14 mol %. In embodiments, the concentration of R₂O in the glasscomposition and the resultant colored glass article may be less than orequal to 25 mol %, less than or equal to 23 mol %, less than or equal to20 mol %, or even less than or equal to 18 mol %. In embodiments, theconcentration of R₂O in the glass composition and the resultant coloredglass article may be greater than or equal to 6 mol % and less than orequal to 25 mol %, greater than or equal to 6 mol % and less than orequal to 23 mol %, greater than or equal to 6 mol % and less than orequal to 20 mol %, greater than or equal to 6 mol % and less than orequal to 18 mol %, greater than or equal to 8 mol % and less than orequal to 25 mol %, greater than or equal to 8 mol % and less than orequal to 23 mol %, greater than or equal to 8 mol % and less than orequal to 20 mol %, greater than or equal to 8 mol % and less than orequal to 18 mol %, greater than or equal to 10 mol % and less than orequal to 25 mol %, greater than or equal to 10 mol % and less than orequal to 23 mol %, greater than or equal to 10 mol % and less than orequal to 20 mol %, greater than or equal to 10 mol % and less than orequal to 18 mol %, greater than or equal to 12 mol % and less than orequal to 25 mol %, greater than or equal to 12 mol % and less than orequal to 23 mol %, greater than or equal to 12 mol % and less than orequal to 20 mol %, greater than or equal to 12 mol % and less than orequal to 18 mol %, greater than or equal to 14 mol % and less than orequal to 25 mol %, greater than or equal to 14 mol % and less than orequal to 23 mol %, greater than or equal to 14 mol % and less than orequal to 20 mol %, or even greater than or equal to 14 mol % and lessthan or equal to 18 mol %, or any and all sub-ranges formed from any ofthese endpoints.

In embodiments, the difference between R₂O and Al₂O₃ (i.e. R₂O (mol%)−Al₂O₃ (mol %)) in the glass composition may be adjusted to produce adesired observable color (e.g., pink, purple, red, or orange). Alongwith the temperature and time of the heat treatment, the analyzedR₂O—Al₂O₃ of the resultant colored glass article may correlate with theobservable color of the colored glass article after heat treatment, asdiscussed herein. In embodiments, R₂O—Al₂O₃ in the glass composition andthe resultant colored glass article may be greater than or equal to −5mol % and less than or equal to 7 mol %. In embodiments, R₂O—Al₂O₃ inthe glass composition and the resultant colored glass article may begreater than or equal to −3 mol % and less than or equal to 6 mol %. Inembodiments, R₂O—Al₂O₃ in the glass composition and the resultantcolored glass article may be greater than or equal to −1 mol % and lessthan or equal to 5 mol %. In embodiments, R₂O—Al₂O₃ in the glasscomposition and the resultant colored glass article may be greater thanor equal to −5 mol % and less than or equal to 1.5 mol %. Inembodiments, R₂O—Al₂O₃ in the glass composition and the resultantcolored glass article may be greater than or equal to −3 mol % and lessthan or equal to 1.5 mol %. In embodiments, R₂O—Al₂O₃ in the glasscomposition and the resultant colored glass article may be greater thanor equal to 1.5 mol % and less than or equal to 7 mol %. In embodiments,R₂O—Al₂O₃ in the glass composition and the resultant colored glassarticle may be greater than or equal to 1.5 mol % and less than or equalto 5 mol %. In embodiments, R₂O—Al₂O₃ in the glass composition and theresultant colored glass article may be greater than or equal to −5 mol%, greater than or equal to −3, greater than or equal to −1 mol %,greater than or equal to 0 mol %, or even greater than or equal to 1.5.In embodiments, R₂O—Al₂O₃ in the glass composition and the resultantcolored glass article may be less than or equal to 7 mol %, less than orequal to 5 mol %, less than or equal to 3 mol %, or even less than orequal to 1.5 mol %. In embodiments, R₂O—Al₂O₃ in the glass compositionand the resultant colored glass article may be greater than or equal to−5 mol % and less than or equal to 7 mol %, greater than or equal to −5mol % and less than or equal to 5 mol %, greater than or equal to −5 mol% and less than or equal to 3 mol %, greater than or equal to −5 mol %and less than or equal to 1.5 mol %, greater than or equal to −3 mol %and less than or equal to 7 mol %, greater than or equal to −3 mol % andless than or equal to 5 mol %, greater than or equal to −3 mol % andless than or equal to 3 mol %, greater than or equal to −3 mol % andless than or equal to 1.5 mol %, greater than or equal to −1 mol % andless than or equal to 7 mol %, greater than or equal to −1 mol % andless than or equal to 5 mol %, greater than or equal to −1 mol % andless than or equal to 3 mol %, greater than or equal to −1 mol % andless than or equal to 1.5 mol %, greater than or equal to 0 mol % andless than or equal to 7 mol %, greater than or equal to 0 mol % and lessthan or equal to 5 mol %, greater than or equal to 0 mol % and less thanor equal to 3 mol %, greater than or equal to 0 mol % and less than orequal to 1.5 mol %, greater than or equal to 1.5 mol % and less than orequal to 7 mol %, greater than or equal to 1.5 mol % and less than orequal to 5 mol %, or even greater than or equal to 1.5 mol % and lessthan or equal to 3 mol %, or any and all sub-ranges formed from any ofthese endpoints.

The glass compositions and the resultant colored glass articlesdescribed herein may further comprise ZrO₂. ZrO₂ may act as a colorantin addition to Au, producing colored glass articles that may be, forexample, red in color. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to0.01 mol % and less than or equal to 2 mol % ZrO₂. In embodiments, theglass composition and the resultant colored glass article may comprisegreater than or equal to 0.1 mol % and less than or equal to 1.5 mol %ZrO₂. In embodiments, the concentration of ZrO₂ in the glass compositionmay be greater than or equal to 0 mol %, greater than or equal to 0.01mol %, greater than or equal to 0.1 mol %, or even greater than or equalto 0.2 mol %. In embodiments, the concentration of ZrO₂ in the glasscomposition may be less than or equal to 2 mol %, less than or equal to1.5 mol %, less than or equal to 1 mol %, less than or equal to 0.75 mol%, or even less than or equal to 0.5 mol %. In embodiments, theconcentration of ZrO₂ in the glass composition may be greater than orequal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1.5 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0 mol % and less than or equal to 0.75 mol %, greater than orequal to 0 mol % and less than or equal to 0.5 mol %, greater than orequal to 0.01 mol % and less than or equal to 2 mol %, greater than orequal to 0.01 mol % and less than or equal to 1.5 mol %, greater than orequal to 0.01 mol % and less than or equal to 1 mol %, greater than orequal to 0.01 mol % and less than or equal to 0.75 mol %, greater thanor equal to 0.01 mol % and less than or equal to 0.5 mol %, greater thanor equal to 0.1 mol % and less than or equal to 2 mol %, greater than orequal to 0.1 mol % and less than or equal to 1.5 mol %, greater than orequal to 0.1 mol % and less than or equal to 1 mol %, greater than orequal to 0.1 mol % and less than or equal to 0.75 mol %, greater than orequal to 0.1 mol % and less than or equal to 0.5 mol %, greater than orequal to 0.2 mol % and less than or equal to 2 mol %, greater than orequal to 0.2 mol % and less than or equal to 1.5 mol %, greater than orequal to 0.2 mol % and less than or equal to 1 mol %, greater than orequal to 0.2 mol % and less than or equal to 0.75 mol %, or even greaterthan or equal to 0.2 mol % and less than or equal to 0.5 mol %, or anyand all sub-ranges formed from any of these endpoints. In embodiments,the glass composition and the resultant colored glass article may besubstantially free or free of ZrO₂.

The glass compositions and the resultant colored glass articlesdescribed herein may further comprise Fe₂O₃. Fe₂O₃ may also act as acolorant in addition to Au, producing colored glass articles that may,for example, be pink or red in color. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 0.01 mol % and less than or equal to 1 mol % Fe₂O₃. Inembodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 0.05 mol % and less thanor equal to 1 mol % Fe₂O₃. In embodiments, the concentration of Fe₂O₃ inthe glass composition may be greater than or equal to 0 mol %, greaterthan or equal to 0.01 mol %, or even greater than or equal to 0.05 mol%. In embodiments, the concentration of Fe₂O₃ in the glass compositionmay be less than or equal to 1 mol %, less than or equal to 0.75 mol %,less than or equal to 0.5 mol %, or even less than or equal to 0.25 mol%. In embodiments, the concentration of Fe₂O₃ in the glass compositionmay be greater than or equal to 0 mol % and less than or equal to 1 mol%, greater than or equal to 0 mol % and less than or equal to 0.75 mol%, greater than or equal to 0 mol % and less than or equal to 0.5 mol %,greater than or equal to 0 mol % and less than or equal to 0.25 mol %,greater than or equal to 0.01 mol % and less than or equal to 1 mol %,greater than or equal to 0.01 mol % and less than or equal to 0.75 mol%, greater than or equal to 0.01 mol % and less than or equal to 0.5 mol%, greater than or equal to 0.01 mol % and less than or equal to 0.25mol %, greater than or equal to 0.05 mol % and less than or equal to 1mol %, greater than or equal to 0.05 mol % and less than or equal to0.75 mol %, greater than or equal to 0.05 mol % and less than or equalto 0.5 mol %, or even greater than or equal to 0.05 mol % and less thanor equal to 0.25 mol %, or any and all sub-ranges formed from any ofthese endpoints. In embodiments, the glass composition and the resultantcolored glass article may be substantially free or free of Fe₂O₃.

The glass compositions and the resultant colored glass articlesdescribed herein may further comprise one or more fining agents. Inembodiments, the fining agents may include, for example, SnO₂. Inembodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 0.01 mol % and less thanor equal to 1 mol % SnO₂. In embodiments, the glass composition and theresultant colored glass article may comprise greater than or equal to0.05 mol % and less than or equal to 0.75 mol % SnO₂. In embodiments,the concentration of SnO₂ in the glass composition may be greater thanor equal to 0 mol %, greater than or equal 0.01 mol % or greater than orequal to 0.05 mol %. In embodiments, the concentration of SnO₂ in theglass composition may less than or equal to 1 mol %, less than or equalto 0.75 mol %, less than or equal to 0.5 mol %, or even less than orequal to 0.25 mol %. In embodiments, the concentration of SnO₂ in theglass composition may be greater than or equal to 0 mol % and less thanor equal to 1 mol %, greater than or equal to 0 mol % and less than orequal to 0.75 mol %, greater than or equal to 0 mol % and less than orequal to 0.5 mol %, greater than or equal to 0 mol % and less than orequal to 0.25 mol %, greater than or equal to 0.01 mol % and less thanor equal to 1 mol %, greater than or equal to 0.01 mol % and less thanor equal to 0.75 mol %, greater than or equal to 0.01 mol % and lessthan or equal to 0.5 mol %, greater than or equal to 0.01 mol % and lessthan or equal to 0.25 mol %, greater than or equal to 0.05 mol % andless than or equal to 1 mol %, greater than or equal to 0.05 mol % andless than or equal to 0.75 mol %, greater than or equal to 0.05 mol %and less than or equal to 0.5 mol %, or even greater than or equal to0.01 mol % and less than or equal to 0.25 mol %, or any and allsub-ranges formed from any of these endpoints. In embodiments, the glasscomposition and the resultant colored glass article may be substantiallyfree or free of SnO₂.

In embodiments, the glass composition and the resultant colored glassarticle may include alkaline earth oxides, such as MgO, ZnO, CaO, SrO,and BaO.

In embodiments, the concentration of MgO in the glass composition andthe resultant colored glass article may be greater than or equal to 0mol % or even greater than or equal to 0.5 mol %. In embodiments, theconcentration of MgO in the glass composition and the resultant coloredglass article may be less than or equal to 2 mol % or even less than orequal to 1 mol %. In embodiments, the concentration of MgO in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0.5 mol % and less than or equal to 2 mol %, or even greaterthan or equal to 0.5 mol % and less than or equal to 1 mol %, or any andall sub-ranges formed from any of these endpoints. In embodiments, theglass composition and the resultant colored glass article may besubstantially free or free of MgO.

In embodiments, the concentration of ZnO in the glass composition andthe resultant colored glass article may be greater than or equal to 0mol % or even greater than or equal to 0.5 mol %. In embodiments, theconcentration of ZnO in the glass composition and the resultant coloredglass article may be less than or equal to 2 mol % or even less than orequal to 1 mol %. In embodiments, the concentration of ZnO in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0.5 mol % and less than or equal to 2 mol %, or even greaterthan or equal to 0.5 mol % and less than or equal to 1 mol %, or any andall sub-ranges formed from any of these endpoints. In embodiments, theglass composition and the resultant colored glass article may besubstantially free or free of ZnO.

In embodiments, the concentration of CaO in the glass composition andthe resultant colored glass article may be greater than or equal to 0mol % or even greater than or equal to 0.5 mol %. In embodiments, theconcentration of CaO in the glass composition and the resultant coloredglass article may be less than or equal to 2 mol % or even less than orequal to 1 mol %. In embodiments, the concentration of CaO in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0.5 mol % and less than or equal to 2 mol %, or even greaterthan or equal to 0.5 mol % and less than or equal to 1 mol %, or any andall sub-ranges formed from any of these endpoints. In embodiments, theglass composition and the resultant colored glass article may besubstantially free or free of CaO.

In embodiments, the concentration of SrO in the glass composition andthe resultant colored glass article may be greater than or equal to 0mol % or even greater than or equal to 0.5 mol %. In embodiments, theconcentration of SrO in the glass composition and the resultant coloredglass article may be less than or equal to 2 mol % or even less than orequal to 1 mol %. In embodiments, the concentration of SrO in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0.5 mol % and less than or equal to 2 mol %, or even greaterthan or equal to 0.5 mol % and less than or equal to 1 mol %, or any andall sub-ranges formed from any of these endpoints. In embodiments, theglass composition and the resultant colored glass article may besubstantially free or free of SrO.

In embodiments, the concentration of BaO in the glass composition andthe resultant colored glass article may be greater than or equal to 0mol % or even greater than or equal to 0.5 mol %. In embodiments, theconcentration of BaO in the glass composition and the resultant coloredglass article may be less than or equal to 2 mol % or even less than orequal to 1 mol %. In embodiments, the concentration of BaO in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % and less than or equal to 2 mol %, greater than orequal to 0 mol % and less than or equal to 1 mol %, greater than orequal to 0.5 mol % and less than or equal to 2 mol %, or even greaterthan or equal to 0.5 mol % and less than or equal to 1 mol %, or any andall sub-ranges formed from any of these endpoints. In embodiments, theglass composition and the resultant colored glass article may besubstantially free or free of BaO.

In embodiments, the glass composition and the resultant colored glassarticle may include Cl, which may enable growth of particular Auparticles. In embodiments, the concentration of Cl in the glasscomposition and the resultant colored glass article may be greater thanor equal to 0 mol % or even greater than or equal to 0.1 mol %. Inembodiments, the concentration of Cl in the glass composition and theresultant colored glass article may be less than or equal to 0.5 mol %or even less than or equal to 0.25 mol %. In embodiments, theconcentration of Cl in the glass composition and the resultant coloredglass article may be greater than or equal to 0 mol % and less than orequal to 0.5 mol %, greater than or equal to 0 mol % and less than orequal to 0.25 mol %, greater than or equal to 0.1 mol % and less than orequal to 0.5 mol %, or even greater than or equal to 0.1 mol % and lessthan or equal to 0.25 mol %, or any and all sub-ranges formed from anyof these endpoints. In embodiments, the glass composition and theresultant colored glass article may be substantially free or free of Cl.

In embodiments, the glass composition and the resultant colored glassarticle may be substantially free or free of MgO, CaO, ZnO, Cl, orcombinations thereof.

The glass compositions and the resultant colored glass articlesdescribed herein further comprise Au as a colorant to achieve thedesired color. In embodiments, the glass composition and the resultantcolored glass article may comprise greater than or equal to 1×10⁻⁶ mol %and less than or equal to 1 mol % Au. In embodiments, the glasscomposition and the resultant colored glass article may comprise greaterthan or equal to 0.0001 mol % and less than or equal to 0.1 mol % Au. Inembodiments, the concentration of Au in the glass composition and theresultant colored glass article may be greater than or equal to 1×10⁻⁶mol %, greater than or equal to 1×10⁵ mol %, greater than or equal to0.0001 mol %, greater than or equal to 0.0005 mol %, or even greaterthan or equal to 0.001 mol %. In embodiments, the concentration of Au inthe glass composition and the resultant colored glass article may beless than or equal to 1 mol %, less than or equal to 0.75 mol %, lessthan or equal to 0.5 mol %, less than or equal to 0.25 mol %, less thanor equal to 0.1 mol %, less than or equal to 0.05 mol %, or even lessthan or equal to 0.01. In embodiments, the concentration of Au in theglass composition and the resultant colored glass article may be greaterthan or equal to 1×10⁻⁶ mol % and less than or equal to 0.75 mol %,greater than or equal to 1×10⁻⁶ mol % and less than or equal to 0.5 mol%, greater than or equal to 1×10⁻⁶ mol % and less than or equal to 0.25mol %, greater than or equal to 1×10⁻⁶ mol % and less than or equal to0.1 mol %, greater than or equal to 1×10⁻⁶ mol % and less than or equalto 0.05 mol %, greater than or equal to 1×10⁻⁶ mol % and less than orequal to 0.01 mol %, greater than or equal to 1×10⁻⁵ mol % and less thanor equal to 1 mol %, greater than or equal to 1×10⁻⁵ mol % and less thanor equal to 0.75 mol %, greater than or equal to 1×10⁻⁵ mol % and lessthan or equal to 0.5 mol %, greater than or equal to 1×10⁻⁵ mol % andless than or equal to 0.25 mol %, greater than or equal to 1×10⁻⁵ mol %and less than or equal to 0.1 mol %, greater than or equal to 1×10⁻⁵ mol% and less than or equal to 0.05 mol %, greater than or equal to 1×10⁻⁵mol % and less than or equal to 0.01 mol %, greater than or equal to0.0001 mol % and less than or equal to 1 mol %, greater than or equal to0.0001 mol % and less than or equal to 0.75 mol %, greater than or equalto 0.0001 mol % and less than or equal to 0.5 mol %, greater than orequal to 0.0001 mol % and less than or equal to 0.25 mol %, greater thanor equal to 0.0001 mol % and less than or equal to 0.1 mol %, greaterthan or equal to 0.0001 mol % and less than or equal to 0.05 mol %,greater than or equal to 0.0001 mol % and less than or equal to 0.01 mol%, greater than or equal to 0.0005 mol % and less than or equal to 1 mol%, greater than or equal to 0.0005 mol % and less than or equal to 0.75mol %, greater than or equal to 0.0005 mol % and less than or equal to0.5 mol %, greater than or equal to 0.0005 mol % and less than or equalto 0.25 mol %, greater than or equal to 0.0005 mol % and less than orequal to 0.1 mol %, greater than or equal to 0.0005 mol % and less thanor equal to 0.05 mol %, greater than or equal to 0.0005 mol % and lessthan or equal to 0.01 mol %, greater than or equal to 0.001 mol % andless than or equal to 1 mol %, greater than or equal to 0.001 mol % andless than or equal to 0.75 mol %, greater than or equal to 0.001 mol %and less than or equal to 0.5 mol %, greater than or equal to 0.001 mol% and less than or equal to 0.25 mol %, greater than or equal to 0.001mol % and less than or equal to 0.1 mol %, greater than or equal to0.001 mol % and less than or equal to 0.05 mol %, or even greater thanor equal to 0.001 mol % and less than or equal to 0.01 mol %, or any andall sub-ranges formed from any of these endpoints.

In embodiments, the glass compositions and the resultant colored glassarticles described herein may further include tramp materials such asTiO₂, MnO, MoO₃, WO₃, Y₂O₃, CdO, As₂O₃, sulfur-based compounds, such assulfates, halogens, or combinations thereof. In embodiments, the glasscomposition and the resultant colored glass article may be substantiallyfree or free of tramp materials such as TiO₂, MnO, MoO₃, WO₃, Y₂O₃, CdO,As₂O₃, sulfur-based compounds, such as sulfates, halogens, orcombinations thereof. In embodiments, antimicrobial components, chemicalfining agents, or other additional components may be included in theglass compositions and the resultant colored glass articles.

In embodiments, the viscosity of the glass composition may be adjustedto prevent devitrification of the glass composition and formation of Auparticles during melting and forming. Formation of Au particles beforemelting may limit the color gamut that may be achieved by heattreatment. Accordingly, in embodiments, to achieve the desired viscosityand thereby prevent formation of Au particles before melting, the glasscompositions and the resultant glass articles described herein maysatisfy the relationship 5.72*Al₂O₃ (mol %)−21.4*ZnO (mol %)−2.5*P₂O₅(mol %)−35*Li₂O (mol %)−16.6*B₂O₃ (mol %)−20.5*MgO (mol %)−23.3*Na₂O(mol %)−27.9*SrO (mol %)−18.5*K₂O (mol %)−26.3*CaO (mol %) is greaterthan −609 mol %. In embodiments, the glass compositions and theresultant glass articles described herein may satisfy the relationship5.72*Al₂O₃ (mol %)−21.4*ZnO (mol %)−2.5*P₂O₅ (mol %)−35*Li₂O (mol%)−16.6*B₂O₃ (mol %)−20.5*MgO (mol %)−23.3*Na₂O (mol %)−27.9*SrO (mol%)−18.5*K₂O (mol %)−26.3*CaO (mol %) is greater than −609 mol %, greaterthan or equal to −575 mol %, greater than or equal to −550 mol %, oreven greater than or equal to −525 mol %. In embodiments, the glasscompositions and the resultant glass articles described herein maysatisfy the relationship 5.72*Al₂O₃ (mol %)−21.4*ZnO (mol %)−2.5*P₂O₅(mol %)−35*Li₂O (mol %)−16.6*B₂O₃ (mol %)−20.5*MgO (mol %)−23.3*Na₂O(mol %)−27.9*SrO (mol %)−18.5*K₂O (mol %)−26.3*CaO (mol %) is less thanor equal to −400 mol %, less than or equal to −425 mol %, or even lessthan or equal to −450 mol %. In embodiments, the glass compositions andthe resultant glass articles described herein may satisfy therelationship 5.72*Al₂O₃ (mol %)−21.4*ZnO (mol %)−2.5*P₂O₅ (mol%)−35*Li₂O (mol %)−16.6*B₂O₃ (mol %)−20.5*MgO (mol %)−23.3*Na₂O (mol%)−27.9*SrO (mol %)−18.5*K₂O (mol %)−26.3*CaO (mol %) is greater than−609 mol % and less than or equal to −400 mol %, greater then −609 mol %and less than or equal to −425 mol %, greater than −609 mol % and lessthan or equal to −450 mol %, greater than or equal to −575 mol % andless than or equal to −400 mol %, greater than or equal to −575 mol %and less than or equal to −425 mol %, greater than or equal to −575 mol% and less than or equal to −450 mol %, greater than or equal to −550mol % and less than or equal to −400 mol %, greater than or equal to−550 mol % and less than or equal to −425 mol %, greater than or equalto −550 mol % and less than or equal to −450 mol %, greater than orequal to −525 mol % and less than or equal to −400 mol %, greater thanor equal to −525 mol % and less than or equal to −425 mol %, or evengreater than or equal to −525 mol % and less than or equal to −450 mol%, or any and all sub-ranges formed from any of these endpoints.

In embodiments, the process for making a glass article includes heattreating a glass composition described herein at one or more preselectedtemperatures for one or more preselected times to induce glasshomogenization. In embodiments, the heat treatment for making a glassarticle may include (i) heating a glass composition at a rate of 1-100°C./min to glass homogenization temperature; (ii) maintaining the glasscomposition at the glass homogenization temperature for a time greaterthan or equal to 0.25 hour and less than or equal to 4 hours to producea glass article; and (iii) cooling the formed glass article to roomtemperature. In embodiments, the glass homogenization temperature may begreater than or equal to 300° C. and less than or equal to 700° C.

The glass compositions described herein include Au, R₂O, and Al₂O₃. Theconcentrations of R₂O and Al₂O₃ may be adjusted such that the differenceR₂O—Al₂O₃, in combination with Au, produces colored glass articleshaving the desired color (e.g., pink, purple, red, or orange). Inembodiments, the colored glass article may have a transmittance colorcoordinate in the CIELAB color space, as measured at an articlethickness of 1.33 mm under F2 illumination and a 10° standard observerangle, of: L* greater than or equal to 50 and less than or equal to 100;a* greater than or equal to −15 and less than or equal to 25; and b*greater than or equal to −25 and less than or equal to 25.

Relatively smaller concentrations of R₂O—Al₂O₃ (e.g., less than or equalto 1.5 mol %) may result in a blue or purple glass article. Relativelyhigher concentrations of R₂O—Al₂O₃ (e.g., greater than 1.5 mol %) mayresult in an orange or red glass article.

For example, in embodiments, R₂O—Al₂O₃ may be greater than or equal to−5 mol % and less than or equal to 1.5 mol % and b* may be greater thanor equal to −25 and less than or equal to 10. In embodiments, R₂O—Al₂O₃may greater than or equal to −3 mol % and less than or equal to 1.5 mol% and b* may be greater than or equal to −15 and less than or equal to7. In embodiments, R₂O—Al₂O₃ may be greater than or equal to −5 mol %and less than or equal to 1.5 mol %, greater than or equal to −3 mol %and less than or equal to 1.5 mol %, greater than or equal to −1 mol %and less than or equal to 1.5 mol %, or even greater than or equal to 0mol % and less than or equal to 1.5 mol %, or any and all sub-rangesformed from any of these endpoints; and b* may be greater than or equalto −25 and less than or equal to 10, greater than or equal to −25 andless than or equal to 7, greater than or equal to −25 and less than orequal to 5, greater than or equal to −15 and less than or equal to 10,greater than or equal to −15 and less than or equal to 7, greater thanor equal to −15 and less than or equal to 5, greater than or equal to−10 and less than or equal to 10, greater than or equal to −10 and lessthan or equal to 7, or even greater than or equal to −10 and less thanor equal to 5, or any and all sub-ranges formed from any of theseendpoints.

In embodiments, R₂O—Al₂O₃ may be greater than 1.5 mol % and less than orequal to 7 mol % and b* may be greater than or equal to 0 and less thanor equal to 25. In embodiments, R₂O—Al₂O₃ may be greater than 1.5 mol %and less than or equal to 5 mol % and b* may be greater than or equal to0 and less than or equal to 15. In embodiments, R₂O—Al₂O₃ may be greaterthan 1.5 mol % and less than or equal to 7 mol %, greater than 1.5 mol %and less than or equal to 5 mol %, or even greater than 1.5 mol % andless than or equal to 3 mol %, or any and all sub-ranges formed from anyof these endpoints; and b* may be greater than or equal to 0 and lessthan or equal to 25, greater than or equal to 0 and less than or equalto 15, greater than or equal to 0 and less than or equal to 10, greaterthan or equal to 2.5 and less than or equal to 25, greater than or equalto 2.5 and less than or equal to 15, greater than or equal to 2.5 andless than or equal to 10, greater than or equal to 5 and less than orequal to 25, greater than or equal to 5 and less than or equal to 15, oreven greater than or equal to 5 and less than or equal to 10, or any andall sub-ranges formed from any of these endpoints.

In embodiments, the glass composition and the resultant colored glassarticle may comprise greater than or equal to 60 mol % and less than orequal to 70 mol % SiO₂; greater than or equal to 11 mol % and less thanor equal to 17 mol % Al₂O₃; greater than or equal to 2 mol % and lessthan or equal to 8 mol % B₂O₃; greater than or equal to 9 mol % and lessthan or equal to 14 mol % Li₂O; greater than or equal to 2 mol % andless than or equal to 6 mol % Na₂O; greater than or equal to 0.1 mol %and less than or equal to 0.5 mol % K₂O; and greater than or equal to1×10⁻⁶ mol % and less than or equal to 0.05 mol % Au. In theseembodiments, R₂O—Al₂O₃ is greater than or equal to 0 mol % and less thanor equal to 3 mol %, R₂O being the sum of Li₂O, Na₂O, and K₂O.

Different color coordinates within the color gamut may be achieved byaltering the heat treatment cycle used to produce the resultant coloredglass articles. The heat treatment cycle is characterized by thetemperature of the environment (i.e., the oven) and the duration of thecycle (i.e., the time the glass article is exposed to the heatedenvironment). As used herein, the phrase “temperature of the heattreatment cycle” refers to the temperature of the environment (i.e., theoven). In embodiments, glass articles formed from the glass compositionsdescribed herein are heat treated in an isothermal oven to produce theresultant colored glass articles.

In embodiments, the temperature of the heat treatment cycle is greaterthan or equal to 500° C., greater than or equal to 550° C., greater thanor equal to 575° C., greater than or equal to 600° C., greater than orequal to 625° C., or even greater than or equal to 650° C. Inembodiments, the temperature of the heat treatment cycle is less than orequal to 800° C., less than or equal to 775° C., less than or equal to750° C., less than or equal to 725° C., or even less than or equal to700° C. In embodiments, the temperature of the heat treatment cycle isgreater than or equal to 500° C. and less than or equal to 800° C.,greater than or equal to 500° C. and less than or equal to 775° C.,greater than or equal to 500° C. and less than or equal to 750° C.,greater than or equal to 500° C. and less than or equal to 725° C.,greater than or equal to 550° C. and less than or equal to 700° C.,greater than or equal to 550° C. and less than or equal to 800° C.,greater than or equal to 550° C. and less than or equal to 775° C.,greater than or equal to 550° C. and less than or equal to 750° C.,greater than or equal to 550° C. and less than or equal to 725° C.,greater than or equal to 550° C. and less than or equal to 700° C.,greater than or equal to 575° C. and less than or equal to 800° C.,greater than or equal to 575° C. and less than or equal to 775° C.,greater than or equal to 575° C. and less than or equal to 750° C.,greater than or equal to 575° C. and less than or equal to 725° C.,greater than or equal to 575° C. and less than or equal to 700° C.,greater than or equal to 600° C. and less than or equal to 800° C.,greater than or equal to 600° C. and less than or equal to 775° C.,greater than or equal to 600° C. and less than or equal to 750° C.,greater than or equal to 600° C. and less than or equal to 725° C.,greater than or equal to 600° C. and less than or equal to 700° C.,greater than or equal to 625° C. and less than or equal to 800° C.,greater than or equal to 625° C. and less than or equal to 775° C.,greater than or equal to 625° C. and less than or equal to 750° C.,greater than or equal to 625° C. and less than or equal to 725° C.,greater than or equal to 625° C. and less than or equal to 700° C.,greater than or equal to 650° C. and less than or equal to 800° C.,greater than or equal to 650° C. and less than or equal to 775° C.,greater than or equal to 650° C. and less than or equal to 750° C.,greater than or equal to 650° C. and less than or equal to 725° C., oreven greater than or equal to 650° C. and less than or equal to 700° C.,or any and all sub-ranges formed from any of these endpoints.

In embodiments, the duration of the heat treatment cycle is greater thanor equal to 0.25 hour, greater than or equal to 0.5 hour, greater thanor equal 1 hour, or even greater than or equal to 2 hours. Inembodiments, the durations of the heat treatment cycle is less than orequal to 24 hours, less than or equal to 16 hours, less than or equal to8 hours, or even less than or equal to 4 hours. In embodiments, theduration of the heat treatment cycle is greater than or equal to 0.25hour and less than or equal to 24 hours, greater than or equal to 0.25hour and less than or equal to 16 hours, greater than or equal to 0.25hour and less than or equal to 8 hours, greater than or equal to 0.25hour and less than or equal to 4 hours, greater than or equal to 0.5hour and less than or equal to 24 hours, greater than or equal to 0.5hour and less than or equal to 16 hours, greater than or equal to 0.5hour and less than or equal to 8 hours, greater than or equal to 0.5hour and less than or equal to 4 hours, greater than or equal to 1 hourand less than or equal to 24 hours, greater than or equal to 1 hour andless than or equal to 16 hours, greater than or equal to 1 hour and lessthan or equal to 8 hours, greater than or equal to 1 hour and less thanor equal to 4 hours, greater than or equal to 2 hours and less than orequal to 24 hours, greater than or equal to 2 hours and less than orequal to 16 hours, greater than or equal to 2 hours and less than orequal to 8 hours, or even greater than or equal to 2 hours and less thanor equal to 4 hours, or any and all sub-ranges formed from any of theseendpoints.

The colored glass articles formed from the glass compositions describedherein may be any suitable thickness, which may vary depending on theparticular application of the colored glass article. In embodiments, thecolored glass articles may have a thickness greater than or equal to 250μm and less than or equal to 6 mm, greater than or equal to 250 μm andless than or equal to 4 mm, greater than or equal to 250 μm and lessthan or equal to 2 mm, greater than or equal to 250 μm and less than orequal to 1 mm, greater than or equal to 250 μm and less than or equal to750 μm, greater than or equal to 250 μm and less than or equal to 500μm, greater than or equal to 500 μm and less than or equal to 6 mm,greater than or equal to 500 μm and less than or equal to 4 mm, greaterthan or equal to 500 μm and less than or equal to 2 mm, greater than orequal to 500 μm and less than or equal to 1 mm, greater than or equal to500 μm and less than or equal to 750 μm, greater than or equal to 750 μmand less than or equal to 6 mm, greater than or equal to 750 μm and lessthan or equal to 4 mm, greater than or equal to 750 μm and less than orequal to 2 mm, greater than or equal to 750 μm and less than or equal to1 mm, greater than or equal to 1 mm and less than or equal to 6 mm,greater than or equal to 1 mm and less than or equal to 4 mm, greaterthan or equal to 1 mm and less than or equal to 2 mm, greater than orequal to 2 mm and less than or equal to 6 mm, greater than or equal to 2mm and less than or equal to 4 mm, or even greater than or equal to 4 mmand less than or equal to 6 mm, or any and all sub-ranges formed fromany of these endpoints.

As discussed hereinabove, colored glass articles formed from the glasscompositions described herein may have an increased fracture toughnesssuch that the colored glass articles are more resistant to damage. Inembodiments, the colored glass article may have a K_(1c) fracturetoughness, as measured by a CNSB method, prior to ion-exchange, greaterthan or equal to 0.7 MPa·m^(1/2). In embodiments, the colored glassarticle may have a K_(1c) fracture toughness, prior to ion-exchange, asmeasured by a CNSB method greater than or equal to 0.7 MPa·m^(1/2)greater than or equal to 0.8 MPa·m^(1/2), greater than or equal to 0.9MPa·m^(1/2), or even greater than or equal to 1.0 MPa·m^(1/2).

In embodiments, the glass compositions described herein areion-exchangeable to facilitate strengthening the colored glass articlemade from the glass compositions. In typical ion-exchange processes,smaller metal ions in the glass compositions are replaced or “exchanged”with larger metal ions of the same valence within a layer that is closeto the outer surface of the colored glass article made from the glasscomposition. The replacement of smaller ions with larger ions creates acompressive stress within the layer of the colored glass article madefrom the glass composition. In embodiments, the metal ions aremonovalent metal ions (e.g., Li⁺, Na⁺, K⁺, and the like), andion-exchange is accomplished by immersing the glass article made fromthe glass composition in a bath comprising at least one molten salt ofthe larger metal ion that is to replace the smaller metal ion in thecolored glass article. Alternatively, other monovalent ions such as Ag⁺,Tl⁺, Cu⁺, and the like may be exchanged for monovalent ions. Theion-exchange process or processes that are used to strengthen thecolored glass article made from the glass composition may includecontacting the colored glass article with an ion-exchange medium. Inembodiments, the ion-exchange medium may be a molten salt bath. Forexample, the ion-exchange process may include, but is not limited to,immersion in a single bath or multiple baths of like or differentcompositions with optional washing and/or annealing steps betweenimmersions.

Upon exposure to the colored glass article, the ion exchange solution(e.g., KNO₃ and/or NaNO₃ molten salt bath) may, according toembodiments, be at a temperature greater than or equal to 350° C. andless than or equal to 500° C., greater than or equal to 360° C. and lessthan or equal to 450° C., greater than or equal to 370° C. and less thanor equal to 440° C., greater than or equal to 360° C. and less than orequal to 420° C., greater than or equal to 370° C. and less than orequal to 400° C., greater than or equal to 375° C. and less than orequal to 475° C., greater than or equal to 400° C. and less than orequal to 500° C., greater than or equal to 410° C. and less than orequal to 490° C., greater than or equal to 420° C. and less than orequal to 480° C., greater than or equal to 430° C. and less than orequal to 470° C., or even greater than or equal to 440° C. and less thanor equal to 460° C., or any and all sub-ranges between the foregoingvalues. In embodiments, the colored glass article may be exposed to theion exchange solution for a duration greater than or equal to 2 hoursand less than or equal to 24 hours, greater than or equal to 2 hours andless than or equal to 12 hours, greater than or equal to 2 hours andless than or equal to 6 hours, greater than or equal to 8 hours and lessthan or equal to 24 hours, greater than or equal to 6 hours and lessthan or equal to 24 hours, greater than or equal to 6 hours and lessthan or equal to 12 hours, greater than or equal to 8 hours and lessthan or equal to 24 hours, or even greater than or equal to 8 hours andless than or equal to 12 hours, or any and all sub-ranges formed fromany of these endpoints.

In embodiments, a colored glass article made from a glass compositionmay be ion-exchanged to achieve a depth of compression 10 μm or greater,20 μm or greater, 30 μm or greater, 40 μm or greater, 50 μm or greater,60 μm or greater, 70 μm or greater, 80 μm or greater, 90 μm or greater,or 100 μm or greater. In embodiments, the colored glass article madefrom the glass composition may have a thickness “t” and may beion-exchanged to achieve a depth of compression greater than or equal to0.15 t, greater than or equal to 0.17 t, or even greater than or equalto 0.2 t. In embodiments, the colored glass article made from the glasscomposition may have a thickness “t” and may be ion-exchanged to achievea depth of compression less than or equal to 0.3 t, less than or equalto 0.27 t, or even less than or equal to 0.25 t. In embodiments, thecolored glass article made from the glass composition described hereinmay have a thickness “t” and may be ion-exchanged to achieve a depth ofcompression greater than or equal to 0.15 t and less than or equal to0.3 t, greater than or equal to 0.15 t and less than or equal to 0.27 t,greater than or equal to 0.15 t and less than or equal to 0.25 t,greater than or equal to 0.17 t and less than or equal to 0.3 t, greaterthan or equal to 0.17 t and less than or equal to 0.27 t, greater thanor equal to 0.17 t and less than or equal to 0.25 t, greater than orequal to 0.2 t and less than or equal to 0.3 t, greater than or equal to0.2 t and less than or equal to 0.27 t, or even greater than or equal to0.2 t and less than or equal to 0.25 t, or any and all sub-ranges formedfrom any of these endpoints.

The development of this surface compression layer is beneficial forachieving a better crack resistance and higher flexural strengthcompared to non-ion-exchanged materials. The surface compression layerhas a higher concentration of the ions exchanged into the colored glassarticle in comparison to the concentration of the ions exchanged intothe colored glass article for the body (i.e., the area not including thesurface compression) of the colored glass article. In embodiments, thecolored glass article made from the glass composition may have a surfacecompressive stress after ion-exchange strengthening greater than orequal to 300 MPa, greater than or equal to 400 MPa, greater than orequal to 500 MPa, or even greater than or equal to 600 MPa. Inembodiments, the colored glass article made from the glass compositionmay have a surface compressive stress after ion-exchange strengtheningless than or equal to 1 GPa, less than or equal to 900 MPa, or even lessthan or equal to 800 MPa. In embodiments, the colored glass article madefrom the glass composition may have a surface compressive stress afterion-exchange strengthening greater than or equal to 300 MPa and lessthan or equal to 1 GPa, greater than or equal to 300 MPa and less thanor equal to 900 MPa, greater than or equal to 300 MPa and less than orequal to 800 MPa, greater than or equal to 400 MPa and less than orequal to 1 GPa, greater than or equal to 400 MPa and less than or equalto 900 MPa, greater than or equal to 400 MPa and less than or equal to800 MPa, greater than or equal to 500 MPa and less than or equal to 1GPa, greater than or equal to 500 MPa and less than or equal to 900 MPa,greater than or equal to 500 MPa and less than or equal to 800 MPa,greater than or equal to 600 MPa and less than or equal to 1 GPa,greater than or equal to 600 MPa and less than or equal to 900 MPa,greater than or equal to 600 MPa and less than or equal to 800 MPa,

In embodiments, the colored glass articles made from the glasscomposition may have a maximum central tension after ion-exchangestrengthening greater than or equal to 40 MPa, greater than or equal to60 MPa, greater than or equal to 80 MPa, or even greater than or equalto 100 MPa. In embodiments, the colored glass article made from theglass composition may have a maximum central tension after ion-exchangestrengthening less than or equal to 250 MPa, less than or equal to 200MPa, or even less than or equal to 150 MPa. In embodiments, the coloredglass article made from the glass composition may have a maximum centraltension after ion-exchange strengthening greater than or equal to 40 MPaand less than or equal to 250 MPa, greater than or equal to 40 MPa andless than or equal to 200 MPa, greater than or equal to 40 MPa and lessthan or equal to 150 MPa, greater than or equal to 60 MPa and less thanor equal to 250 MPa, greater than or equal to 60 MPa and less than orequal to 200 MPa, greater than or equal to 60 MPa and less than or equalto 150 MPa, greater than or equal to 80 MPa and less than or equal to250 MPa, greater than or equal to 80 MPa and less than or equal to 200MPa, greater than or equal to 80 MPa and less than or equal to 150 MPa,greater than or equal to 100 MPa and less than or equal to 250 MPa,greater than or equal to 100 MPa and less than or equal to 200 MPa, oreven greater than or equal to 100 MPa and less than or equal to 150 MPa,or any and all sub-ranges formed from any of these endpoints. Asutilized herein, central tension refers to a maximum central tensionvalue unless otherwise indicated.

The colored glass articles described herein may be used for a variety ofapplications including, for example, back cover applications in consumeror commercial electronic devices such as smartphones, tablet computers,personal computers, ultrabooks, televisions, and cameras. An exemplaryarticle incorporating any of the colored glass articles disclosed hereinis shown in FIGS. 1 and 2 . Specifically, FIGS. 1 and 2 show a consumerelectronic device 100 including a housing 102 having front 104, back106, and side surfaces 108; electrical components (not shown) that areat least partially inside or entirely within the housing and includingat least a controller, a memory, and a display 110 at or adjacent to thefront surface of the housing; and a cover substrate 112 at or over thefront surface of the housing such that it is over the display. Inembodiments, at least a portion of housing 102, such as the back 106,may include any of the colored glass articles disclosed herein.

Examples

In order that various embodiments be more readily understood, referenceis made to the following examples, which illustrate various embodimentsof the colored glass articles described herein.

Table 1 shows example compositions C1-C26, with the analyzedconcentration (in terms of mol %) of the resultant colored glassarticles.

TABLE 1 Composition C1 C2 C3 C4 C5 C6 SiO₂ 61.21 61.94 62.86 61.81 61.9161.36 Al₂O₃ 14.46 14.48 14.52 15.56 15.54 15.75 B₂O₃ 5.84 5.95 5.92 5.885.89 5.91 Li₂O 11.79 10.95 11.01 11.05 11.02 11.17 Na₂O 6.34 6.32 5.345.34 5.34 5.42 K₂O 0.19 0.19 0.19 0.19 0.19 0.19 MgO 0.01 0.02 0.01 0.020.02 0.02 CaO — — — — — — ZnO — — — — — — ZrO₂ — — — — — — SnO₂ 0.110.11 0.10 0.11 0.05 0.06 Fe₂O₃ — — — — — 0.07 Cl 0.02 0.03 0.02 0.030.02 0.02 Au 0.0005 0.0007 0.0009 0.0008 0.0007 0.0005 R₂O 18.32 17.4616.54 16.58 16.55 16.78 R₂O—Al₂O₃ 3.86 2.98 2.02 1.02 1.01 1.035.72*Al₂O₃— −578.32 −550.38 −528.71 −523.70 −522.93 −529.18 21.4*ZnO—2.5*P₂O₅—35*Li₂O— 16.6*B₂O₃— 20.5*MgO— 23.3*Na₂O— 27.9*SrO—18.5*K₂O—26.3*CaO Composition C7 C8 C9 C10 C11 C12 SiO₂ 61.24 60.87 60.67 60.5460.56 60.70 Al₂O₃ 15.66 16.54 16.47 16.52 16.36 16.27 B₂O₃ 5.89 5.855.84 5.99 6.04 6.01 Li₂O 11.15 11.08 10.97 11.06 11.13 11.12 Na₂O 5.385.34 5.35 5.27 5.28 5.28 K₂O 0.19 0.19 0.19 0.20 0.20 0.19 MgO 0.01 0.020.02 0.02 0.02 0.02 CaO — — — — — — ZnO — — — — — — ZrO₂ 0.32 — 0.310.32 0.32 0.32 SnO₂ 0.05 0.06 0.05 0.05 0.05 0.05 Fe₂O₃ 0.07 — 0.07 — —— Cl 0.02 0.02 0.02 — — — Au 0.0005 0.0007 0.0005 0.0007 0.0008 0.0008R₂O 16.72 16.61 16.51 16.53 16.61 16.59 R₂O—Al₂O₃ 1.06 0.07 0.04 0.010.25 0.32 5.72*Al₂O₃— −527.52 −518.65 −515.27 −518.94 −523.37 −522.8521.4*ZnO— 2.5*P₂O₅—35*Li₂O— 16.6*B₂O₃— 20.5*MgO— 23.3*Na₂O—27.9*SrO—18.5*K₂O— 26.3*CaO Composition C13 C14 C15 C16 C17 C18 SiO₂60.64 60.64 63.76 65.01 65.86 67.01 Al₂O₃ 16.07 15.42 14.39 14.29 14.2813.47 B₂O₃ 6.01 6.04 5.86 5.09 4.36 4.13 Li₂O 11.37 11.50 11.02 10.9610.95 10.92 Na₂O 5.28 5.76 4.24 4.23 4.22 4.20 K₂O 0.19 0.19 0.14 0.140.14 0.14 MgO 0.02 0.02 0.04 0.03 0.02 0.02 CaO — — — — 0.01 0.01 ZnO —— 0.02 — — — ZrO₂ 0.32 0.32 0.48 0.20 0.10 0.04 SnO₂ 0.05 0.05 0.04 0.040.04 0.04 Fe₂O₃ — — — — — — Cl — — — — — — Au 0.0008 0.0008 0.00110.0010 0.0010 0.0010 R₂O 16.84 17.45 15.41 15.33 15.31 15.26 R₂O—Al₂O₃0.77 2.03 1.01 1.04 1.03 1.79 5.72*Al₂O₃— −532.74 −552.69 −503.22−488.03 −475.55 −474.86 21.4*ZnO— 2.5*P₂O₅—35*Li₂O— 16.6*B₂O₃— 20.5*MgO—23.3*Na₂O— 27.9*SrO—18.5*K₂O— 26.3*CaO Composition C19 C20 C21 C22 SiO₂67.59 67.75 67.84 67.89 Al₂O₃ 13.13 13.01 12.96 12.99 B₂O₃ 3.93 3.923.92 3.92 Li₂O 10.94 10.91 10.88 10.77 Na₂O 4.17 4.17 4.17 4.20 K₂O 0.140.14 0.14 0.14 MgO 0.02 0.02 0.01 0.01 CaO 0.01 0.01 0.01 0.01 ZnO 0.000.00 0.00 0.00 ZrO₂ 0.02 0.02 0.01 0.01 SnO₂ 0.04 0.04 0.04 0.04 Fe₂O₃0.00 0.00 0.00 0.00 Cl 0.00 0.00 0.00 0.00 Au 0.0011 0.0014 0.00160.0006 R₂O 15.25 15.22 15.20 15.11 R₂O—Al₂O₃ 2.13 2.21 2.24 2.125.72*Al₂O₃— −473.41 −473.02 −472.32 −468.73 21.4*ZnO— 2.5*P₂O₅—35*Li₂O—16.6*B₂O₃— 20.5*MgO— 23.3*Na₂O— 27.9*SrO—18.5*K₂O— 26.3*CaO CompositionC23 C24 C25 C26 SiO₂ 67.63 63.76 65.86 67.59 Al₂O₃ 13.15 14.39 14.2813.13 B₂O₃ 3.94 5.86 4.36 3.93 Li₂O 10.69 11.02 10.95 10.94 Na₂O 4.214.24 4.22 4.17 K₂O 0.15 0.14 0.14 0.14 MgO 0.01 0.04 0.02 0.02 CaO 0.100.00 0.00 0.00 ZnO 0.00 0.02 0.00 0.00 ZrO₂ 0.02 0.48 0.10 0.02 SnO₂0.04 0.04 0.04 0.04 Fe₂O₃ 0.00 0.00 0.00 0.00 Cl 0.00 0.00 0.00 0.00 Au0.0001 8.3 × 10⁻⁶ 7.7 × 10⁻⁶ 8.0 × 10⁻⁶ R₂O 15.04 15.40 15.31 15.25R₂O—Al₂O₃ 1.90 1.01 1.03 2.12 5.72*Al₂O₃— −468.03 −503.30 −475.27−473.20 21.4*ZnO— 2.5*P₂O₅—35*Li₂O— 16.6*B₂O₃— 20.5*MgO— 23.3*Na₂O—27.9*SrO—18.5*K₂O— 26.3*CaO

Referring now to Table 2, example glass articles A1-A52 having wereformed from example compositions C2-C9 and C15-C23 shown in Table 1 andwere subjected to heat treatment at the temperature and for the periodof time shown in Table 2. The transmittance color coordinate in theCIELAB color space, as measured at an article thickness of 1.33 mm underF2 illumination and a 10° standard observer angle, and the observablecolor of the resultant colored glass articles are shown in Table 2.

TABLE 2 Glass Article A1 A2 A3 A4 A5 A6 Composition C18 C19 C20 C21 C22C23 Heat treatment 550 550 550 550 550 550 temp. (° C.) Heat treatment 88 8 8 8 8 time (hr.) L* 87.39 88.12 86.98 86.12 91.39 96.68 a* 7.72 7.348.39 9.23 4.78 0.00 b* 1.87 4.93 8.07 9.58 3.81 0.80 Observable colororange orange orange orange orange light yellow Glass Article A7 A8 A9A10 A11 A12 Composition C15 C16 C17 C18 C18 C19 Heat treatment 575 575575 575 575 575 temp. (° C.) Heat treatment 2 2 2 8 2 8 time (hr.) L*83.48 92.46 85.94 88.08 91.19 88.2 a* 0.19 0.98 1.68 8.15 3.07 7.80 b*−6.06 −0.93 −4.63 5.71 −0.47 6.51 Observable color blue purple purpleorange pink orange Glass Article A13 A14 A15 A16 A17 A18 Composition C19C20 C20 C21 C22 C22 Heat treatment 575 575 575 575 575 575 temp. (° C.)Heat treatment 2 8 2 8 8 2 time (hr.) L* 89.96 86.7 86.9 85.72 90.5990.98 a* 4.42 8.49 8.50 8.98 5.51 4.33 b* −0.06 9.06 6.59 10.40 4.771.19 Observable color pink orange orange orange orange red Glass ArticleA19 A20 A21 A22 A23 A24 Composition C23 C23 C15 C16 C17 C18 Heattreatment 575 575 600 600 600 600 temp. (° C.) Heat treatment 2 8 2 2 22 time (hr.) L* 96.73 95.89 82.63 83 83.43 88.03 a* 0.03 0.63 3.35 4.275.48 8.35 b* 0.75 1.84 −6.62 −6.11 −5.49 4.10 Observable color yellowpeach purple purple purple orange Glass Article A25 A26 A27 A28 A29 A30Composition C19 C20 C22 C23 C2 C3 Heat treatment 600 600 600 600 625 625temp. (° C.) Heat treatment 2 2 2 2 2 2 time (hr.) L* 87.99 86.66 90.2396.4 89.29 87.6 a* 8.34 8.91 5.53 0.28 5.14 7.22 b* 5.45 8.48 3.52 1.249.97 10.51 Observable color orange orange orange light orange orange redGlass Article A31 A32 A33 A34 A35 A36 Composition C4 C5 C6 C7 C8 C9 Heattreatment 625 625 625 625 625 625 temp. (° C.) Heat treatment 2 2 2 2 22 time (hr.) L* 83 86.74 88.94 87.28 78.03 80.49 a* 11.39 9.76 6.92 9.095.04 6.25 b* 2.59 2.60 4.75 3.44 −9.39 −8.92 Observable color red redred red purple purple Glass Article A37 A38 A39 A40 A41 A42 CompositionC15 C16 C17 C18 C19 C20 Heat treatment 625 625 625 625 625 625 temp. (°C.) Heat treatment 2 2 2 2 2 2 time (hr.) L* 84.25 85.21 85.58 87.587.39 86.09 a* 10.89 10.87 10.81 8.98 8.76 9.27 b* −0.89 0.55 0.90 4.565.39 8.00 Observable color magenta red red orange orange orange GlassArticle A43 A44 A45 A46 A47 A48 Composition C22 C23 C15 C16 C17 C18 Heattreatment 625 625 650 650 650 650 temp. (° C.) Heat treatment 2 2 2 2 22 time (hr.) L* 90.31 95.7 84.63 85.69 86.23 87.42 a* 5.73 0.89 11.1911.18 10.85 9.14 b* 3.85 1.49 −0.12 1.22 1.47 4.40 Observable colororange orange magenta red red orange Glass Article A49 A50 A51 A52Composition C19 C20 C22 C23 Heat treatment 650 650 650 650 temp. (° C.)Heat treatment 2 2 2 2 time (hr.) L* 87.42 86.18 90.14 95.53 a* 8.849.28 6.00 1.04 b* 5.24 8.10 3.89 1.42 Observable color orange orangeorange orange

Referring now to Table 3, example glass articles A53-A114 were formedfrom example compositions C1-C14 and C24-C26 shown in Table 1 and weresubjected to heat treatment at the temperature and for the period oftime shown in Table 3. The observable colors of the resultant coloredglass articles are shown in Table 3.

TABLE 3 Glass Article A53 A54 A55 A56 A57 A58 Composition C1 C2 C3 C4 C5C6 Heat treatment 550 550 550 550 550 550 temp. (° C.) Heat treatment 22 2 2 2 2 time (hr.) Observable red clear, clear, clear clear red colorred red Glass Article A59 A60 A61 A62 A63 A64 Composition C7 C8 C9 C10C11 C12 Heat treatment 550 550 550 550 550 550 temp. (° C.) Heattreatment 2 2 2 2 2 2 time (hr.) Observable red clear clear, clear clearclear color pink Glass Article A65 A66 A67 A68 A69 A70 Composition C13C14 C24 C1 C2 C3 Heat treatment 550 550 550 575 575 575 temp. (° C.)Heat treatment 2 2 8 2 2 2 time (hr.) Observable clear clear, purpleorange orange red color purple Glass Article A71 A72 A73 A74 A75 A76Composition C4 C5 C6 C7 C8 C9 Heat treatment 575 575 575 575 575 575temp. (° C.) Heat treatment 2 2 2 2 2 2 time (hr.) Observable purplepurple red red clear, clear, color red pink Glass Article A77 A78 A79A80 A81 A82 Composition C10 C11 C12 C13 C14 C24 Heat treatment 575 575575 575 575 575 temp. (° C.) Heat treatment 2 2 2 2 2 2 time (hr.)Observable clear, clear, clear, clear, clear, purple color purple purplepurple purple red Glass Article A83 A84 A85 A86 A87 A88 Composition C25C26 C24 C25 C1 C2 Heat treatment 575 575 575 575 600 600 temp. (° C.)Heat treatment 2 2 8 8 2 2 time (hr.) Observable purple red red redorange orange color Glass Article A89 A90 A91 A92 A93 A94 Composition C3C4 C5 C6 C7 C8 Heat treatment 600 600 600 600 600 600 temp. (° C.) Heattreatment 2 2 2 2 2 2 time (hr.) Observable red purple purple red redpurple color Glass Article A95 A96 A97 A98 A99 A100 Composition C9 C10C11 C12 C13 C14 Heat treatment 600 600 600 600 600 600 temp. (° C.) Heattreatment 2 2 2 2 2 2 time (hr.) Observable purple purple purple purplepurple orange color Glass Article A101 A102 A103 A104 A105 A106Composition C24 C25 C26 C24 C25 C26 Heat treatment 600 600 600 625 625625 temp. (° C.) Heat treatment 2 2 2 2 2 2 time (hr.) Observable purplered red red red red color Glass Article A107 A108 A109 A110 CompositionC10 C11 C12 C13 Heat treatment 650 650 650 650 temp. (° C.) Heattreatment 2 2 2 2 time (hr.) Observable purple purple clear, purplecolor purple Glass Article A111 A112 A113 A114 Composition C14 C24 C25C26 Heat treatment 650 650 650 650 temp. (° C.) Heat treatment 2 2 2 2time (hr.) Observable orange red red red color

Referring now to FIGS. 3 and 4 , plots show the relationship ofR₂O—Al₂O₃ and a* and b*, respectively, of example glass articlesA29-A44. As shown in FIG. 3 , a* was a positive number, regardless ofthe R₂O—Al₂O₃ value, thereby resulting in observable colors towards redside of the CIELAB color space. As shown in FIG. 4 , as R₂O—Al₂O₃increased, b* increased, thereby shifting the observable colors fromblue to yellow. For example, example glass articles A35 and A36, formedfrom example compositions C8 and C9 having an analyzed R₂O—Al₂O₃ of 0.07mol % and 0.04 mol %, respectively, had a b* of −9.39 and −8.92,respectively, resulting in observably purple glass articles. Exampleglass articles A29 and A30, formed from example glass compositions C2and C3 having an analyzed R₂O—Al₂O₃ of 2.98 mol % and 2.02 mol %,respectively, had a b* of 9.97 and 10.51, respectively, resulting in anobservably orange glass article and an observably red glass article.

Moreover, example glass articles A33 and A34, formed from example glasscompositions C6 and C7 including Fe₂O₃ and ZrO₂, respectively, had anobservable red color.

As indicated by Tables 2 and 3 and FIGS. 3 and 4 , the analyzedR₂O—Al₂O₃ may be adjusted, additional components may be added to theglass composition, and the glass article may be subjected to a certainheat treatment to provide a desired colored glass article.

It will be apparent to those skilled in the art that variousmodifications and variations may be made to the embodiments describedherein without departing from the spirit and scope of the claimedsubject matter. Thus, it is intended that the specification cover themodifications and variations of the various embodiments described hereinprovided such modification and variations come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A glass composition comprising: greater than orequal to 50 mol % and less than or equal to 80 mol % SiO₂; greater thanor equal to 7 mol % and less than or equal to 25 mol % Al₂O₃; greaterthan or equal to 1 mol % and less than or equal to 15 mol % B₂O₃;greater than or equal to 7 mol % and less than or equal to 20 mol %Li₂O; greater than or equal to 0.5 mol % and less than or equal to 12mol % Na₂O; greater than 0 mol % and less than or equal to 1 mol % K₂O;and greater than or equal to 1×10⁻⁶ mol % and less than or equal to0.0016 mol % Au, wherein: R₂O—Al₂O₃ is greater than or equal to −5 mol %and less than or equal to 5 mol %, R₂O being the sum of Li₂O, Na₂O, andK₂O.
 2. The glass composition of claim 1, wherein R₂O—Al₂O₃ is greaterthan or equal to −3 mol % and less than or equal to 5 mol %.
 3. Theglass composition of claim 1, wherein the glass composition comprisesgreater than or equal to 0.0001 mol % and less than or equal to 0.001mol % Au.
 4. The glass composition of claim 1, wherein R₂O is greaterthan or equal to 6 mol % and less than or equal to 25 mol %.
 5. Theglass composition of claim 1, wherein the glass composition comprisesgreater than or equal to 0.01 mol % and less than or equal to 2 mol %ZrO₂.
 6. The glass composition of claim 1, wherein 5.72*Al₂O₃ (mol%)−21.4*ZnO (mol %)−2.5*P₂O₅ (mol %)−35*Li₂O (mol %)−16.6*B₂O₃ (mol%)−20.5*MgO (mol %)−23.3*Na₂O (mol %)−27.9*SrO (mol %)−18.5*K₂O (mol%)−26.3*CaO (mol %) is greater than −609 mol %.
 7. The glass compositionof claim 1, wherein the glass composition comprises greater than orequal to 0.01 mol % and less than or equal to 1 mol % SnO₂.
 8. The glasscomposition of claim 1, wherein the glass composition comprises greaterthan or equal to 7 mol % and less than or equal to 18 mol % Li₂O.
 9. Theglass composition of claim 1, wherein the glass composition comprisesgreater than or equal to 1 mol % and less than or equal to 12 mol %Na₂O.
 10. The glass composition of claim 1, wherein the glasscomposition comprises greater than or equal to 0.1 mol % and less thanor equal to 0.5 mol % K₂O.
 11. The glass composition of claim 1, whereinthe glass composition comprises greater than or equal to 2 mol % andless than or equal to 12 mol % B₂O₃.
 12. A colored glass articlecomprising the glass composition of claim
 1. 13. The colored glassarticle of claim 12, wherein the colored glass article has atransmittance color coordinate in the CIELAB color space, as measured atan article thickness of 1.33 mm under F2 illumination and a 100 standardobserver angle, of: L* greater than or equal to 50 and less than orequal to 100; a* greater than or equal to −15 and less than or equal to25; and b* greater than or equal to −25 and less than or equal to 25.14. The colored glass article of claim 12, wherein the colored glassarticle has a thickness greater than or equal to 250 μm and less than orequal to 6 mm.
 15. The colored glass article of claim 12, wherein thecolored glass article is an ion-exchanged colored glass article.
 16. Thecolored glass article of claim 15, wherein the ion-exchanged coloredglass article has a depth of compression 10 μm or greater.
 17. Thecolored glass article of claim 15, wherein the ion-exchanged coloredglass article has a surface compressive stress greater than or equal to300 MPa.
 18. The colored glass article of claim 15, wherein theion-exchanged colored glass article has a maximum central tensiongreater than or equal to 40 MPa.
 19. A consumer electronic device,comprising: a housing having a front surface, a back surface, and sidesurfaces; and electrical components provided at least partially withinthe housing, the electrical components including at least a controller,a memory, and a display, the display being provided at or adjacent thefront surface of the housing; wherein the housing comprises the coloredglass article of claim
 15. 20. A method of heat treating the glasscomposition of claim 1, the method comprising: heat treating the glasscomposition to form a glass article, subjecting the glass article to aheat treatment cycle at a temperature greater than or equal to 500° C.and less than or equal to 800° C. and a duration greater than or equalto 0.25 hour and less than or equal to 24 hours to produced the coloredglass article.